Solutions Manual Starting Out with Programming Logic and Design 6th Edition By Tony Gaddis All Chapt

Solutions

Part 1: Python Instructor Manual Part 2: Solutions to Programming Exercises Part 3: Language Companions Part 4: Answers to Review Questions

Solutions Manual Part 1 Python Instructor Manual

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Python Instructor Manual Lab 1: Input, Processing, and Output What is Python?

Python is a general purpose language created in the early 1990s. It has become popular in business and academic applications.

Installing Python The Python interpreter can run Python programs that are saved in files, or interactively execute Python statements that are typed at the keyboard. Python comes with a program named IDLE that simplifies the process of writing, executing, and testing programs. The labs primarily use the IDLE environment.

The most current version of Python can be downloaded from the following site: http://www.python.org/download/releases/. After downloading and installing, start the IDLE Environment for Python.

If the Edit window for entering code does not come up, go to Options, Configure IDLE, click on the General tab, and under Startup Preferences select Open Edit Window. Close and reopen the Environment. You should only have to do this the first time running Python.

Python Scripts Python runs in two modes: interactive and script mode. The labs will direct students to use script mode, in which the interpreter reads the contents of a file that contains Python statements. The statements are created and saved in a file with a .py extension.

Using the IDLE 1. In the Edit window of Python, start by saving your file. You must add the .py extension along with your file name. Doing so makes your program ready for compiling and also identifies keywords.

2. After entering code, you can check your code by clicking Run and Check Module.

3. Click Run and Run Module to see your program execute. The program will execute in the Python Shell.

The Print Function To print something onto the screen, use the print function. Anything in single quotation marks is printed to the screen. If the value of a variable needs to be displayed, you can simply list the variable name. If a string literal also needs to be displayed, you can separate the message and variable name with commas. Double quotation marks can

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also be used and should be when using an apostrophe in the string literal. Basic use is as follows: print('Hello world') print(variableName) print('Value of variable', variableName) print('Value of variable,' variableName, 'with a continued sentence.') print("It's a nice day outside") Program Comments Program comments are preceded by a # sign. For example: # This is my first program print('Hello world') # prints a message to the screen Variables Variables in Python are created with an assignment statement. There is no need to assign it a data type, however; the value assigned to the variable determines the data type. For example, room will be stored as an int because it was assigned a whole number. In the following program, you must assign the variable a value before it can be used. For example: room = 503 rentalRate = 87.99 hotelName = 'Logic Lodge'

# will be stored as an int # will be stored as a float # will be stored as a string

print('I am staying in room number', room) print('The rate at', hotelName, 'is', rentalRate) Additionally, normal variable naming rules apply.

Input You use Python's built-in input function to read input from the keyboard. The input function reads a piece of data that has been entered at the keyboard and returns that piece of data, as a string, back to the program. For example: employee_name = input('Enter your name: ') The input function always returns the user's input as a string, even if the user enters numeric data. For example, suppose you call the input function and the user types the number 72 and pressed the Enter key. The value that is returned from the input function is the string '72'.

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Fortunately, Python has built-in functions that you can use to convert a string to a numeric type. Use the int() function to convert a string to an integer, or the float() function to convert a string to a floating-point (real) number. Example: hours = int(input('How many hours did you work? ')) pay_rate = float(input('Enter your hourly pay rate: ')) Calculations Standard mathematical operators are used in Python.

Symbol

Operation

Description

+ * /

Addition Subtraction Multiplication Division

//

Integer Division Remainder Exponent

Adds two numbers Subtracts one number from another Multiplies one number by another Divides one number by another and gives the quotient as a real number Divides one number by another and gives the quotient as an integer Divides one number by another and gives the remainder Raises a number to a power

% **

Calculations must be written with the expression on the right such as: Total = 10 + 56 10 + 56 = Total

# the correct way # the wrong way

If the calculation needs to yield a floating-point value, one of the values must have a decimal point. For example: Total = 10.0 + 56

# the value of 66.0 will be displayed

The standard order of operations applies in Python and parentheses can be used to group expressions.

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Solutions Lab 1: Input, Processing, and Output Note to Instructor: This lab accompanies Chapter 2 of Starting Out with Programming Logic & Design. Material in the chapter should have been covered prior to lab assignment. In addition, students should have had instruction on using a flowcharting application such as Raptor and instruction on using the IDLE environment for Python.

Evaluation: The instructor should be present to answer any questions and observe the student performing the lab. The student should turn in a hard copy (paper) or soft copy (email) of their work. To minimize the number of attachments or individual files created for this lab, space is set aside in the lab for students to insert completed exercises.

Directions are provided to students on copying and pasting.

Learning Objectives for this lab include: 1. Identify pseudocode keywords.

2. Identify flowcharting symbols.

3. How to declare variables with appropriate data types.

4. How to assign values to variables.

5. How to take in input from the computer user.

6. How display output to the screen.

7. How to document code.

8. How to process calculations.

Lab 1.1 through 1.4 uses the following programming problem.

Write a program that will take in basic information from a student, including student name, degree name, number of credits taken so far, and the total number of credits required in the degree program. The program will then calculate how many credits are needed to graduate. Display should include the student name, the degree name, and credits left to graduate.

Lab 1.5 and 1.6 are Programming Challenge Problems.

Students were asked to write the Algorithm, Pseudocode, Flowchart, and Python code for the Programming Challenge problems.

Starting Out with Programming Logic and Design

Lab 1.1 – Algorithms Step 1: Examine the following algorithm. (Reference: See Designing a Program in Chapter 2).

1. Get the student name.

2. Get the degree program name.

3. Subtract the number of credits taken so far from the required credits for the degree.

4. Get the number of credits required for the degree program.

5. Get the number of credits the student has taken so far.

6. Display the input information in Step 1 and 2.

7. Display the calculated information.

Step 2: What logic error do you spot and how would you fix it?

Step 3 cannot be processed until Step 4 and 5 are processed.

1. Get the student name.

2. Get the degree name.

3. Get the number of credits required for the degree program.

4. Get the number of credits the student has taken so far.

5. Subtract the number of credits taken for the required credits for the degree.

6. Display the input information in Step 1 and 2.

7. Display the calculated information in Step 5.

Step 3: What steps require user interaction (Ex: user must type in some input)?

Step 1, Step 2, Step 3, and Step 4

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Lab 1.2 –Pseudocode Step 1: This program is most easily solved using just five variables. Identify potential problems with the following variables declared in the pseudocode. Assume that the college has the ability to offer half credits. (Reference: See Variable Names in Chapter 2.).

Variable Name Declare Real creditsTaken Declare Real credits Degree

Problem (Yes or No) No Yes

Declare Int creditsLeft

Yes

Declare Real studentName Declare String degreeName

Yes No

If Yes, what’s wrong?

No spaces are allowed in variable name Wrong data type. Since this is used in a formula that uses Reals, it too should be a real. It is also possible a college would grant a half credit.

Wrong data type. Should be String.

Step 2: Complete the pseudocode by writing the two missing lines. (Reference: See Prompting the User, Chapter 2).

Display "Enter student name."

Input studentName Display "Enter degree program."

Input degreeName Display "Enter credits required for the degree."

Input creditsDegree Display "Enter the number of credits taken so far."

Input creditsTaken

Step 3: What two things are wrong with the following calculation? (Reference: Variable Assignment and Calculations, Chapter 2). creditsLeft = creditsTaken – creditsDegree

There is no Set keyword used prior to the equation.

Expression is backwards, should be Set creditsLeft = creditsDegree - creditsTaken Step 4: Write the exact output you would expect from the following line of code if the user of the program enters "Bill Jones". (Reference: Displaying Items, Chapter 2).

Display "The student's name is ", studentName

Starting Out with Programming Logic and Design The student’s name is Bill Jones Step 5: Write the exact output you would expect from the following line of code if the user of the program enters a degree that is 63 credits in total and they have taken 40 credits. (Reference: Displaying Screen Output and Displaying Multiple Items With One Display Statement, Chapter 2).

Display "This program requires ", creditsDegree, " credits and they have taken ", creditsTaken, " so far."

This program requires 63 credits and they have taken 40 so far.

Step 6: Complete the following pseudocode to solve the programming problem.

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// This program takes in student information and calculates // how many credits the student has left before graduation. // Information is then printed to the screen.

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// Declare variables Declare Real creditsTaken Declare Real creditsDegree Declare Real creditsLeft Declare String studentName Declare String degreeName

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// Asks for user input Display "Enter student name."

Input studentName Display "Enter degree program."

Input degreeName Display "Enter credits required for degree completion."

Input creditsDegree Display "Enter credits taken so far."

Input creditsTaken

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// Calculates remaining credits Set creditsLeft = creditsDegree – creditsTaken

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// Display Student Name, Degree Program, and Credits Left Display "The student’s name is ", studentName Display "The degree program is ", degreeName Display "This means there are ", creditsLeft, " left until graduation."

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Lab 1.3 –Flowcharts Note to Instructor: Steps 1 – 9 walk students through the process of using Raptor and designing a flowchart.

Step 10 requires students to show their completed flowchart. Variable names and statements will vary from student to student. Also, the lab can be completed using a different flowcharting application, such as Visio. If so, the sample solution below will look a little different, but should still have the same fundamental steps.

Instructors should grade on clear variable names, proper flow of program, the correct calculation, and the right output. Below is a sample solution to the programming problem.

Step 10:

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Lab 1-4: Python Code Note to Instructor: Steps 1 - 5 require students to think critically about input and output and answer questions.

Steps 6 - 18 in this lab require the student to write Python code to create a program.

Their final program is required in Step 19. Variable names and statements will vary from student to student. Instructors should grade the final program on clear variable names, proper flow of program, the correct calculation, and the right output.

Step 1: Examine the following line of code. What do you expect as output to the screen? studentName = input('Enter student name. ')

Enter student name.

Step 2: Examine the following line of code. What type of value do you expect the user of the program to enter? creditsDegree = int(input('Enter credits required for degree. '))

A number such as 63.

Step 4: If the user of the program types Bill Jones to the question in Step 1, what do you expect the output to the screen to be when the following line of code processes? print('The student\'s name is', studentName)

The student’s name is Bill Jones

Step 5: Examine the following line of code. If the program requires 63 credits, and the student has 20 left, what do you expect the output to the screen to be? print('The program requires', creditsDegree, 'credits and they have taken', creditsTaken, 'credits so far.')

The program requires 63 credits and they have taken 43 credits so far.

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Step 19: Complete Python code. # This program takes in student information and calculates # the number of credits the student has left before # graduation.

Information is then printed to the screen. # Input data studentName = input('Enter student name. ') degreeName = input('Enter degree program. ') creditsDegree = int(input('Enter credits required for degree. ')) creditsTaken = int(input('Enter credits taken so far. ')) # The calculation creditsLeft = creditsDegree - creditsTaken # The output # print with an empty set of parentheses prints a blank # line to the screen print() print('The student\'s name is', studentName) print('The degree program is', degreeName) print('The program requires', creditsDegree, 'and they have taken', creditsTaken, 'so far.') print('This means there are', creditsLeft, 'left to take.')

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Lab 1.5 – Programming Challenge 1 – Team Average Team Average A college wants you to write a program for them that will calculate the average number of wins for their football team over the past five years. The user of the program should be able to enter the number of wins each year. The program will calculate the average number of wins during that five-year period and display that information to the screen.

Algorithm 1.

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Get the number of wins for year 1.

Get the number of wins for year 2.

Get the number of wins for year 3.

Get the number of wins for year 4.

Get the number of wins for year 5.

Add up wins for all years and divide by total number of years.

Display the calculated information in Step 6.

Pseudocode 1.

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// This program calculates the average number of wins over the past // five years for a football team.

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// Declare variables Declare Real year1 Declare Real year2 Declare Real year3 Declare Real year4 Declare Real year5 Declare Real yearlyAverage

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// Ask for user input Display "Enter number of wins for year 1. " Input year1 Display "Enter number of wins for year 2. " Input year2 Display "Enter number of wins for year 3. " Input year3 Display "Enter number of wins for year 4. " Input year4 Display "Enter number of wins for year 5. " Input year5

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// Calculates the average Set yearlyAverage = (year1 + year2 + year3 + year4 + year5) / 5

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// Display requested information

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Display "The average number of wins each year over", "the last five years is ", yearlyAverage

Flowchart Start

A

Declare Real year1 Declare Real year2 Declare Real year3 Declare Real year4 Declare Real year5 Declare Real yearlyAverage

Display “Enter number of wins for year 4.”

Input year4

Display “Enter number of wins for year 1.”

Display “Enter number of wins for year 5” Input year1 Input year5 Display “Enter number of wins for year 2.”

Set yearlyAverage = (year1 + year2 + year3 + year4 + year5) / 5 Input year2

Display “Enter number of wins for year 3.”

Display “The average number of wins each year over the last five years is”, yearlyAverage

Input year3

A

Stop

Starting Out with Programming Logic and Design Python Code # This program will calculate the average number of wins # over the past five years for a football team. # Input data year1 = int(input('Enter number of wins for year 1. ')) year2 = int(input('Enter number of wins for year 2. ')) year3 = int(input('Enter number of wins for year 3. ')) year4 = int(input('Enter number of wins for year 4. ')) year5 = int(input('Enter number of wins for year 5. ')) # The calculation yearlyAverage = (year1 + year2 + year3 + year4 + year5) / 5 #The output print() print('Average number of wins each year over the last five years:', yearlyAverage)

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Lab 1.6 – Programming Challenge 2 – Pedometer Calculator Pedometer Calculator A dietician wants you to write a program that will calculate the number of calories a person uses by walking at a slow pace for a mile; however, the user will have only the distance given by a pedometer, which is measured in steps and not miles.

Assume each mile a person walks is equivalent to 2000 steps, and that for every mile walked, a person loses 65 calories. Allow the user of the program to enter the number of steps taken throughout the day. The program will calculate the distance in miles and the number of calories lost. The user of the program should also be able to enter the day of the week the data is being calculated for. The day of the week, the distance in miles, and the calories lost should then be displayed to the screen.

Algorithm 1.

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Get the day of the week.

Get the number of steps reported on the pedometer.

Divide the number of steps taken by 2000, which is the number of steps per mile.

Multiply the result of Step 3 times 65, which is the number of calories burned per mile.

5. Display the input information in Step 1.

6. Display the calculated information in Step 4 and 5.

Pseudocode 1.

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// This program will calculate how many calories are burned // based on the number of steps taken throughout a day. // This is based on 2000 steps equals 1 mile and // 1 mile of walking burns 65 calories. // Declare variables Declare String weekDay Declare Integer stepsTaken Declare Integer caloriesLost Declare Real milesWalked

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// Ask for user input Display "Enter the day of the week. " Input weekDay Display "Enter the number of steps reported on the pedometer. " Input stepsTaken

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// The calculations

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Set milesWalked = stepsTaken / 2000 Set caloriesLost = milesWalked * 65

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// Display the output

Starting Out with Programming Logic and Design 19.

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Display "The following is data for, " weekDay Display "Walking ", milesWalked, " miles results in ", caloriesLost, " calories lost."

Flowchart Start

Declare String weekDay Declare Integer stepsTaken Declare Integer caloriesLost Declare Real milesWalked

Display “Enter the day of the week.”

Input weekDay

Display “Enter the number of steps reported on the pedometer.”

Input stepsTaken

Set milesWalked = stepsTaken / 2000

Set caloriesLost = milesWalked * 65

Display “The following is data for “, weekDay

Display “Walking “, milesWalked, “ miles results in “, caloriesLost, “ calories burned.”

Stop

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Starting Out with Programming Logic and Design Python Code # This program will calculate the number of calories a person # burns for each mile walked. However, the input is read in steps. # 2000 steps equals 1 mile and a person burns 65 calories per mile, # on average. # Input data weekDay = input('Enter the day of the week. ') stepsTaken= int(input('Enter the number of steps reported on the pedometer. ')) # The calculation milesWalked = stepsTaken / 2000 caloriesLost = milesWalked * 65 # The output print() # \t tabs the line over print('\t\tThe following is data for', weekDay) print() # Display the output print('Walking', milesWalked, 'miles resulted in', caloriesLost, 'calories lost.')

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Starting Out with Programming Logic and Design

Lab 1: Input, Processing, and Output This lab accompanies Chapter 2 of Starting Out with Programming Logic & Design.

Name:

Lab 1.1 – Algorithms Critical Review An algorithm is a set of well-designed logical steps that must take place in order to solve a problem.

The flow the algorithm takes is sequential. For example, before you process calculations, all data needed should be retrieved.

This lab requires you to think about the steps that take place in a program by writing algorithms. Read the following program prior to completing the lab.

Write a program that will take in basic information from a student, including student name, degree name, number of credits taken so far, and the total number of credits required in the degree program. The program will then calculate how many credits are needed to graduate. Display should include the student name, the degree name, and credits left to graduate.

Step 1: Examine the following algorithm.

1. Get the student name.

2. Get the degree program name.

3. Subtract the number of credits taken so far from the required credits for the degree.

4. Get the number of credits required for the degree program.

5. Get the number of credits the student has taken so far.

6. Display the input information in Step 1 and 2.

7. Display the calculated information.

Step 2: What logic error do you spot and how would you fix it?

Step 3: What steps require user interaction (Ex: user must type in some input)?

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Starting Out with Programming Logic and Design

Lab 1.2 – Pseudocode Critical Review Pseudocode is an informal language that has no syntax rules and is not meant to be compiled or executed.

The flow the program takes is sequential. For example, before you ask for input, you should display what information you want from the user. // Comments are done by putting two forward slashes // before the lines you want to document. Comments // are used to explain code.

Variables are named storage locations.

Declare is the keyword used before naming a variable. Data types are: Real for decimal numbers, Integer for whole numbers, and String for a series of characters.

Follow the rules for naming variables: (1) must be one word, no spaces, (2) usually no punctuation characters, only letters and numbers, and (3) name cannot start with a number.

Display is the keyword used to print something to the screen. Any information needed to be displayed to the user should be put inside quotation marks such as: Display "This is how you print something to the screen" When using display to print both a string and the value of a variable, a comma is used, such as: Display "Here is the average: ", average.

Input is the keyword used to get the user to enter data. The data value entered by the user will be placed in the variable that follows the keyword input such as Input variableName.

Set is the keyword used before a calculation. Standard math operators are used, such as + - * / MOD ^. Operators can be combined in one calculation, but it is wise to group expressions together using parentheses. Remember the order of operations.

Some examples are: Set sale = price – discount Set average = (test1 + test2 + test3) / 3

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Starting Out with Programming Logic and Design

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This lab requires you to think about the steps that take place in a program by writing pseudocode. Read the following program prior to completing the lab.

Write a program that will take in basic information from a student, including student name, degree name, number of credits taken so far, and the total number of credits required in the degree program. The program will then calculate how many credits are needed to graduate. Display should include the student name, the degree name, and credits left to graduate.

Step 1: This program is most easily solved using just five variables. Identify potential problems with the following variables declared in the pseudocode. Assume that the college has the ability to offer half credits. (Reference: See Variable Names, Chapter 2 39-40).

Variable Name

Problem (Yes or No)

If Yes, what's wrong?

Declare Real creditsTaken Declare Real credits Degree Declare Int creditsLeft Declare Real studentName Declare String degreeName

Step 2: Complete the pseudocode by writing the two missing lines. (Reference: See the section on Prompting the User, Chapter 2).

Display "Enter student name."

Display "Enter degree program."

Input degreeName Input creditsDegree Display "Enter the number of credits taken so far."

Step 3: What two things are wrong with the following calculation? (Reference: See Variable Assignment and Calculations in Chapter 2). creditsLeft = creditsTaken – creditsDegree

Step 4: Write the exact output you would expect from the following line of code if the user of the program enters “Bill Jones”. (Reference: See Displaying Multiple Items in Chapter 2).

Starting Out with Programming Logic and Design

Display "The student's name is ", studentName

Step 5: Write the exact output you would expect from the following line of code if the user of the program enters a degree that is 63 credits in total and they have taken 40 credits. (Reference: See Displaying Multiple Items in Chapter 2).

Display "This program requires ", creditsDegree, " credits and they have taken ", creditsTaken, " so far."

Step 6: Complete the following pseudocode to solve the programming problem.

1. //This program takes in student information and calculates 2. //how many credits the student has left before graduation.

3. //Information is then printed to the screen.

4. //Declare variables 5. Declare Real creditsTaken 6.

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10. //Ask for user input 11. Display "Enter student name."

12. Input studentName 13.

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19. //Calculate remaining credits 20.

21. //Display student name, degree program, and credits left.

22. Display "The student's name is ", studentName 23.

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Starting Out with Programming Logic and Design

Lab 1.3 – Flowcharts Critical Review A flowchart is a diagram that graphically depicts the steps that take place in a program. Symbols are used to depict the various steps that need to happen within a program. Flow lines are used between the symbols to indicate the flow of the program.

Ovals are used as terminal symbols, which indicate a start and stop to a program.

Parallelograms, the data symbol, are used for input and display statements.

Rectangles, the process symbol, are used for calculations and variable declarations.

On page connectors are used to link a flowchart that continues on the same page. The connecting system starts with the letter A, whereas A would appear in the two connectors that show the flow.

The statements inside the data and the process symbols can be written similarly to the statements used in pseudocode.

Connector

This lab requires you to think about the steps that take place in a program by designing a flowchart. While designing flowcharts can be done with paper and pencil, one mistake often requires a lot of erasing. Therefore, a flowcharting application such as Raptor, Flowgorithm, or Visio should be used. This lab will give you a brief overview of Raptor.

Read the following program prior to completing the lab.

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Starting Out with Programming Logic and Design Write a program that will take in basic information from a student, including student name, degree name, number of credits taken so far, and the total number of credits required in the degree program. The program will then calculate how many credits are needed to graduate. Display should include the student name, the degree name, and credits left to graduate.

Step 1: Start Raptor; notice the Raptor screen. This window is your primary tool for creating a flowchart. Prior to adding symbols, save your document by clicking on File and then Save. Select your location and save the file as Lab 1-3. The .rap file extension will be added automatically.

Step 2: Notice the MasterConsole screen. This window is used to show your program output once your flowchart is completed. The Clear button will clear the console to view a fresh run of your program.

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Starting Out with Programming Logic and Design Step 3: Return to the Raptor screen to begin adding symbols into your flowchart. Your flowchart should follow the pseudocode in Lab 1-2, Step 6. While a rectangle is normally used for declaring variables, there is no easy way to do this in Raptor. Since this is an important part of flowcharting, we will do this using a comment box. To do this, Right-Click on the Start symbol and select Comment. In the Enter Comment box, type the variables your program will need. Below is a start to how it should look.

Step 4: The next step in your flowchart should be to ask for user input. Click the Input Symbol on the Left and Drag and Drop to the flow line between Start and Stop. Double Click on the Input Symbol to begin entering information. Enter Enter student name in the top box. Enter studentName in the variable box. Below is how it should look.

Step 5: Continue the Step 4 directions for all your input statements, changing each Input symbol to reflect the appropriate user interaction.

Step 6: The next step in your flowchart is to process any calculations that exist. Click on the Assignment symbol and drag it to the flow line between the last input statement and the end symbol. Double click on the Assignment symbol to enter your code. In the Set box, put the name of your storage variable. In the To box, put the expression part of your formula. Below is how it should look.

Step 7: The next step in your flowchart is to display the requested output to the screen.

Click the Output symbol and drag it to the flow line between the assignment statement and the end symbol. Double click on the Output symbol to enter your code. Under Output Type, select Output Expression since we want to display both a sentence and the contents of a variable. In the box, type "Student name is " + studentName.

Below is how it should look once you click Done.

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Starting Out with Programming Logic and Design

Step 8: Continue the Step 7 directions for all your output statements, changing each Output symbol to reflect the appropriate requested output information.

Step 9: Once your flowchart is complete, click on Run and then Execute to Completion on the Raptor menu. Follow the flow of your program to see if it processes properly.

Your Master Console window should show output similar to Student name is Bill Jones The degree program is Computer Programming Credits left to graduation is 39 ----Run finished----

Step 10: The final step is to insert your finished flowchart in the space below. Inside Raptor, select File and the Print to Clipboard from the menu. Inside Word in the space below, select Edit and Paste.

PASTE FLOWCHART HERE

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Starting Out with Programming Logic and Design

Lab 1.4 – Python Code Critical Review Comments in Python are preceded by the # sign.

Input of strings into a variable is done using the input function. This function converts the input to a series of characters so they can be used later in the program. This is written as a statement such as: stringVariable = input('Enter a word. ') The input function always returns the user's input as a string, even if the user enters numeric data. If you want your program to read a numeric value as input, you must use a conversion function along with the input function. To convert input to an integer, you use the int() conversion function, and to convert input to a real number, you use the float() conversion function. For example, the following statement reads input from the user, converts that input to an integer, and assigns the integer value to a variable named number: number = int(input('Enter a number. ')) The following statement reads input from the user, converts that input to an real number (also known as a floating-point number), and assigns the integer value to a variable named number: number = float(input('Enter a number. ')) Equations are written similarly to the method used in pseudocode, but without the Set keyword. For example: total = apples + oranges Complex formulas should use parentheses to group processes. In addition, if input values are taken in as integers, but will be used to calculate a decimal value, they must be converted to real values. For example: average = (test1 + test2) / 2 To display information to the screen, the print function is used with the string, which is written within single quotation marks. If the value of a variable needs to displayed after the string, a comma separates the two. For example: print('The average is', average)

This lab requires you to translate your work in the pseudocode and flowchart to actual code using Python. Read the following program prior to completing the lab.

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Write a program that will take in basic information from a student, including student name, degree name, number of credits taken so far, and the total number of credits required in the degree program. The program will then calculate how many credits are needed to graduate. Display should include the student name, the degree name, and credits left to graduate.

Step 1: Examine the following line of code. What do you expect as output to the screen? studentName = input('Enter student name. ')

Step 2: Examine the following line of code. What type of value do you expect the user of the program to enter? creditsDegree = int(input('Enter credits required for degree.'))

Step 3: If the user of the program types Bill Jones to the question in Step 1, what do you expect the output to the screen to be when the following line of code processes? print('The student\'s name is', studentName)

Step 4: Examine the following code. If the program requires 63 credits, and the student has 20 left, what do you expect the output to the screen to be? print('The program requires', creditsDegree, 'credits and they have taken', creditsTaken, 'credits so far.')

Step 5: Start the IDLE Environment for Python. If the Edit window for entering code does not come up, go to Options, Configure IDLE, click on the General tab, and under Startup Preferences select Open Edit Window. Close and reopen the Environment. Prior

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to entering code, save your file by clicking on File and then Save. Select your location and save this file as Lab1-4.py. Be sure to include the .py extension.

Step 6: Code should start with documentation. Document the first few lines of your program to include your name, the date, and a brief description of what the program does.

Each line that you want to comment out must begin with a # sign. For example: # Sally Smith # January 15 # This program ...

Step 7: After documentation, enter the following line of code into your program. studentName = input('Enter student name. ')

Step 8: On the menu, select Run and then Run Module. Observe your program in action. If you get a syntax error, you must fix it before you are able to run your program.

Click OK and review the highlighted syntax error to fix it.

Step 9: Repeat Step 7, but change the statement so that it asks the user to enter their degree name. It is up to you whether you want to repeat Step 8 each time you code a line.

It is recommended for beginning programmers so they can immediately identify syntax errors. Also, one syntax error at a time seems better than many all at once.

Step 10: Next, you should write the code that will ask the user how many credits are required in the degree. This can be done using the input function since it is a numeric value. Enter the following line of code into your program. creditsDegree = int(input('Enter the number of credits required for the degree. '))

Step 11: Repeat Step 10 but change the statement so that it asks the user to enter the number of credits they have taken so far.

Step 12: Next, add your calculation. This is done very simply with the following code. creditsLeft = creditsDegree – creditsTaken

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Step 13: Add the following line of code to your program. print('The student's name is', studentName)

Step 14: If you have not tested your program in a while, now is a good time to try it out.

Go to Run and Run Module and observe what happens. SYNTAX ERROR! Step 15: While nothing stands out as being wrong in Step 14, notice that the word student's is actually causing the problem. To the language, the apostrophe looks as if it is the end of the statement. Since it is not, it must be quoted out by putting a \ in front of it. Change the line to the following. print('The student\'s name is', studentName)

Step 16: Finish your code by printing the remaining of the requested statements. Your final output might look like the following.

Enter student name. Bill Jones Enter degree name. Computer Programming Enter the number of credits required for the degree. 63 Enter the number of credits taken so far. 24 The student's name is Bill Jones The degree name is Computer Programming There are 39.0 credits left until graduation.

Step 17: When your code is complete and runs properly, on the Menu, go to Edit and then Select All, then Edit and Copy. Paste the code below.

PASTE CODE HERE

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Lab 1.5 – Programming Challenge 1 – Team Average Write the Algorithm, Pseudocode, Flowchart, and Python code for the following programming problem.

Team Average A college wants you to write a program for them that will calculate the average number of wins for their football team over the past five years. The user of the program should be able to enter the number of wins each year. The program will calculate the average number of wins during that five year period and display that information to the screen.

The Algorithm TYPE ALGORITHM HERE The Pseudocode TYPE PSEUDOCODE HERE The Flowchart PASTE FLOWCHART HERE The Python Code PASTE CODE HERE

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Lab 1.6 – Programming Challenge 2 – Pedometer Calculator Write the Algorithm, Pseudocode, Flowchart, and Python code for the following programming problem.

Pedometer Calculator A dietician wants you to write a program that will calculate the number of calories a person can lose by walking at a slow pace for a mile; however, the user will have only the distance given by a pedometer, which is measured in steps and not miles. Assume each mile a person walks is equivalent to 2000 steps, and that for every mile walked, a person loses 65 calories. Allow the user of the program to enter the number of steps taken throughout the day. The program will calculate the distance in miles and the number of calories lost. The user of the program should also be able to enter the day of the week the data is being calculated for.

The day of the week, the distance in miles, and the calories lost should then be displayed to the screen.

The Algorithm TYPE ALGORITHM HERE The Pseudocode TYPE PSEUDOCODE HERE The Flowchart PASTE FLOWCHART HERE The Python Code PASTE CODE HERE

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Python Instructor Manual Lab 2: Decisions and Boolean Logic Relational Operators Relational operators used in Python are as follows: Operator > < >= <= == !=

Meaning Greater than Less than Greater than or equal to Less than or equal to Equal to Not equal to

The >= and <= Operators Two of the operators, >= and <=, test for more than one relationship. The >= operator determines whether the operand on its left is greater than or equal to the operand on its right. The <= operator determines whether the operand on its left is less than or equal to the operand on its right.

The == Operator The == operator determines whether the operand on its left is equal to the operand on its right. If the values referenced by both operands are the same, the expression is true.

The != Operator The != operator is the not equal to operator. It determines whether the operand on its left is not equal to the operand on its right, which is the opposite of the == operator.

The if Statement In Python we use the if statement to write a single alternative decision structure. Here is the general format of the if statement: if condition: statement statement etc.

For simplicity, we will refer to the first line as the if clause. The if clause begins with the word if, followed by a condition, which is an expression that will be evaluated as either true or false. A colon appears after the condition. Beginning at the next line

Python Instructor Manual is a block of statements. (Recall from Chapter 3 that all the statements in a block must be consistently indented. This indentation is required because the Python interpreter uses it to tell where the block begins and ends.)

When the if statement executes, the condition is tested. If the condition is true, the statements that appear in the block following the if clause are executed. If the condition is false, the statements in the block are skipped.

Comparing Strings Python allows you to compare strings. Remind students that strings are case sensitive so when entering test values, if the month is compared to April, the A must be capital. For example: if birthMonth == 'April': print('Congratulations, the birth month is April.')

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Solutions Lab 2: Decisions and Boolean Logic Note to Instructor: This lab accompanies Chapter 3 of Starting Out with Programming Logic & Design, with a focus on if statements and relational operators. Material in the chapter should have been covered prior to lab assignment.

Evaluation: The instructor should be present to answer any questions and observe the student performing the lab. The student should turn in a hard copy (paper) or soft copy (email) of their work.

Learning Objectives for this lab include: 1. Understand how relational operators function.

2. Understand how Boolean expressions process.

3. Learn how to write an if statement in pseudocode, flowcharts, and Python code.

Lab 2.1 walks the student through the process of evaluating Boolean expressions.

Labs 2.2, 3.3, and 3.4 use the following programming problem.

A retail company assigns a $5000 store bonus if monthly sales are $100,000 or more. Additionally, if their sales exceed 125% or more of their monthly goal of $90,000, then all employees will receive a message stating that they will get a day off.

Lab 2.5 uses the following programming problem.

Write a program that will ask the user to guess a person's age, their height in inches, and their birth month. Your program will compare the entered values to the following and print the appropriate responses.

The Secret Answers age = 25 height = 72 birthMonth = 'April'

The Comparison If the guessed age is less than or equal to 25 If the guessed height is greater than or equal to 72 If the guessed birth month is equal to April

The Printed Response Congratulations, the age is 25 or less Congratulations, the height is 72 or more Congratulations, the birth month is April

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Lab 2.1 – Evaluating Conditions Step 1: Consider the following values set to variables.

• myAge = 32 • yourAge = 18 • myNumber = 81 • yourNumber = 17 • votingAge = 18 • myName = "Katie" • yourName = "Bob" Step 2: Based on the values to the variables in Step 1, do the following conditions result in a true or false statement?

The condition myAge >= yourAge yourAge > myAge myAge == 45 yourAge == votingAge votingAge >= yourAge myAge <= votingAge myName != yourName myNumber <= myAge yourNumber >= myAge yourNumber != 17

True or False True False False True True False True True False False

Step 3: Based on the values to the variables in Step 1, what is the expected output?

Hint: The output will either be what is printed to the screen, or "nothing."

The condition If myName == yourName Then print "We have the same name" End If If myAge >= yourAge Then print "I am older or equal to your age" End If If myName != "Katie" Then print "That is not my name" End If If myName == "Katie" Then print "That is my name" End If If myNumber == 17 Then print "My number is 17" End If If myNumber >=80 Then

Expected Output Nothing I am older or equal to your age Nothing That is my name Nothing My number is 80 or more

Starting Out with Programming Logic and Design print "My number is 80 or more" End If If yourNumber <= yourAge Then print "Your number is less than or equal to your age" End If If myNumber < yourNumber Then print "My number is less" End If If yourAge >= votingAge Then print "You can vote" End If If myAge < yourAge Then print "I am younger" End If

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Your number is less than or equal to your age Nothing You can vote Nothing

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Lab 2.2 – Pseudocode and Decisions Step 1: This program is easiest when solved using just one variable. Declare the variables that you will need in the program, using the proper data type and documenting the purpose. Depending on your programming style, you may find that additional variables are useful. If that is the case, adjust your program as necessary.

Variable Name

Purpose

Real monthlySales

Stores the monthly sales

Step 2: The following algorithm outlines the program's major actions. Study this algorithm and make sure you understand each step.

1.

Get the amount of monthly sales from the user.

2.

If the monthly sales are greater than $100,000, display a message saying that a $5,000 bonus has been achieved.

3.

If the monthly sales are greater than 125% of $90,000, displaying a message saying that all employees get an extra day off. (Hint: 125% of $90,000 is $112,500.)

Step 3: Complete the following pseudocode by writing the missing lines. (Reference: Writing a Decision Structure in Pseudocode, Chapter 3). // Declare variables Declare Real monthlySales // Get the monthly sales.

Display "Enter the total sales for the month."

Input monthlySales // Determine whether a bonus is awarded.

If monthlySales >= 100000 Then Display "You get a bonus of $5,000!!!"

End If // Determine whether all employees get an extra day off. // Write your pseudocode here: If monthlySales >= 112500 Then Display "All employees get an extra day off!!!"

End If

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Lab 2.3 – Flowcharts Note to Instructor: Steps 1 – 8 walk students through the process of using Raptor and designing a flowchart.

Step 9 requires students to show their completed flowchart. Variable names and statements will vary from student to student. Also, the lab can be completed using a different flowcharting application such as Visio. If so, the sample solution below will look a different, but should still have the same fundamental steps.

Instructors should grade on clear variable names, proper flow of program, the correct calculation, and the right output. Below is a sample solution to the programming problem.

Starting Out with Programming Logic and Design

Lab 2.4 – Python Code Note to Instructor: Steps 1 – 8 in this lab require students to write Python code to create a program. Their final program is required in Step 9.

Step 9: # Student Name # Date # This program determines if a bonus and an extra day off # will be awarded # Get the monthly sales monthlySales = float(input('Enter the monthly sales $')) # Determine if there is a bonus. if monthlySales >= 100000: print("You have earned a $5,000 bonus!!!") # Determine if employees get an extra day off. if monthlySales >= 112500: print("All employees get a day off!!!")

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Lab 2.5 – Programming Challenge 1 – Guess the Secrets The Pseudocode // Declare variables Declare Integer age Declare Integer height Declare String birthMonth // Get the user's guess for age.

Display "Enter your guess for age: " Input age // Get the user's guess for height.

Display "Enter your guess for height in inches: " Input height // Get the user's guess for birth month.

Display "Enter your guess for birth month: " Input birthMonth // Determine if the age is correct and display the results.

If age <= 25 Then Display "Congratulations, the age is 25 or less."

End If // Determine if the height is correct and display the results.

If height >= 72 Then Display "Congratulations, the height is 72 or more."

End If // Determine if the birth month is correct and display the results.

If birthMonth == "April" Then Display "Congratulations, the birth month is April."

End If

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Starting Out with Programming Logic and Design The Flowchart

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Starting Out with Programming Logic and Design

The Python Code # Secret Answers # Get the guess for age age = int(input('Enter your guess for age: ')) # Get the guess for height height = int(input('Enter your guess for height in inches: ')) # Get the guess for birth month. birthMonth = input('Enter your guess for birth month: ') if age <= 25: print('Congratulations, the age is 25 or less.') if height >= 72: print('Congratulations, the height is 72 or more.') if birthMonth == 'April': print('Congratulations, the birth month is April.')

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Lab 2: Decisions and Boolean Logic This lab accompanies Chapter 3 of Starting Out with Programming Logic & Design.

Name:

Lab 2.1 – Evaluating Conditions Critical Review A relational operator determines whether a specific relationship exists between two values.

Relational operators Operator > < >= <= = = !=

Meaning Greater than Less than Greater than or equal to Less than or equal to Equal to Not equal to

Boolean Expression X > Y X < Y X >= Y X <= Y X = = Y X != Y

This lab requires you to think about possible true and false conditions using if statements.

Step 1: Consider the following values set to variables.

• myAge = 32 • yourAge = 18 • myNumber = 81 • yourNumber = 17 • votingAge = 18 • myName = "Katie" • yourName = "Bob" Step 2: Based on the values to the variables in Step 1, do the following conditions result in a true or false statement? (Reference: Boolean Expressions and Relational Operators Chapter 3).

The condition myAge >= yourAge yourAge > myAge myAge == 45 yourAge == votingAge

True or False

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votingAge <= yourAge myAge <= votingAge myName != yourName myNumber <= myAge yourNumber >= myAge yourNumber != 17

Step 3: Based on the values to the variables in Step 1, what is the expected output?

Hint: The output will be either what is printed to the screen, or nothing. (Reference: Boolean Expressions and Relational Operators Chapter 3).

The condition If myName == yourName Then print "We have the same name" End If If myAge >= yourAge Then print "I am older or equal to your age" End If If myName != "Katie" Then print "That is not my name" End If If myName == "Katie" Then print "That is my name" End If If myNumber == 17 Then print "My number is 17" End If If myNumber >=80 Then print "My number is 80 or more" End If If yourNumber <= yourAge Then print "Your number is less than or equal to your age" End If If myNumber < yourNumber Then print "My number is less" End If If yourAge >= votingAge Then print "You can vote" End If If myAge < yourAge Then print "I am younger" End If

Expected Output

Starting Out with Programming Logic and Design

Lab 2.2 – Pseudocode and Decisions Critical Review Questions are often asked using an if statement such as if X > Y, whereas the question asked is "is X greater than Y"?

The general structure of an if statement is If condition Then Statement Statement Etc. End If

This lab requires you to think about the steps that take place in a program by writing pseudocode. Read the following program prior to completing the lab.

A retail company assigns a $5000 store bonus if monthly sales are $100,000 or more. Additionally, if their sales exceed 125% of their monthly goal of $90,000, then all employees will receive a message stating that they will get an extra day off.

Step 1: This program is easiest when solved using just one variable. Declare the variables that you will need in the program, using the proper data type and documenting the purpose. Depending on your programming style, you may find additional variables are useful. If that is the case, adjust your program as necessary.

Variable Name

Purpose Stores the monthly sales

Step 2: The following algorithm outlines the program's major actions. Study this algorithm and make sure you understand each step.

1.

Get the amount of monthly sales from the user.

2.

If the monthly sales are greater than $100,000, display a message saying that a $5,000 bonus has been achieved.

3.

If the monthly sales are greater than 125% of $90,000, displaying a message saying that all employees get an extra day off. (Hint: 125% of $90,000 is $112,500.)

Step 3: Complete the following pseudocode by writing the missing lines. (Reference: Writing a Decision Structure in Pseudocode, Chapter 3).

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Starting Out with Programming Logic and Design // Declare variables Declare Real monthlySales // Get the monthly sales.

Display "Enter the total sales for the month."

Input monthlySales // Determine whether a bonus is awarded.

If monthlySales >= 100000 Then Display "You get a bonus of $5,000!!!"

End If // Determine whether all employees get an extra day off. // Write your pseudocode here:

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Lab 2.3 – Flowcharts Critical Review The flowchart symbol used to indicate some condition is a diamond. An if statement is called a single alternative decision structure. The code will only process if the decision is true.

This lab requires you to convert your pseudocode in Lab 2.2 to a flowchart. Use an application such as Raptor, Flowgorithm, or Visio.

Step 1: Start Raptor and save your document as Lab 3-3. The .rap file extension will be added automatically. Start by adding a Comment box that declares your variables. Here is how your Comment box should look.

Step 2: Add the necessary steps to enter the monthly sales. At this point, your flowchart might look like the following:

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Step 5: Next you will add the steps to determine whether a bonus of $5000 is awarded.

Click the Selection symbol and add it after the Input symbol. Double click on the diamond symbol and add the code to determine if monthlySales is greater than or equal to 100000. The enter selection condition should be written as follows:

Step 6: Drag an output symbol and drop it on the True line (the "Yes" line). Double click on the output box and add text that prints "You get a bonus of $5000!!!". Your module should like as follows:

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Step 7: Repeat the process in Step 6 to add the steps to determine whether all employees get an extra day off.

Step 8: When your program is complete, test the following monthly sales and ensure that the output matches the following. If your output is different, then review your decision statements.

Monthly Sales monthlySales = 102500 monthlySales = 90000 monthlySales= 112500

Expected Output You get a bonus of $5000!!! <nothing> You get a bonus of $5000!!!

All employees get an extra day off!!!

Step 9: The final step is to insert your finished flowchart in the space below. Inside Raptor, select File and the Print to Clipboard from the menu. Inside Word in the space below, select Edit and Paste. You will have to do this for each module you created.

PASTE FLOWCHART HERE

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Lab 2.4 – Python Code Critical Review In Python we use the if statement to write a single alternative decision structure. Here is the general format of the if statement: if condition: statement statement etc.

For simplicity, we will refer to the first line as the if clause. The if clause begins with the word if, followed by a condition, which is an expression that will be evaluated as either true or false. A colon appears after the condition.

Beginning at the next line is a block of statements.

When the if statement executes, the condition is tested. If the condition is true, the statements that appear in the block following the if clause are executed. If the condition is false, the statements in the block are skipped.

When strings are evaluated in a condition, single quotation marks are used. For example: name1 = 'Mary' name2 = 'Mark' if name1 != name2: print 'The names are not the same.' if name1 == ‘Mary’ print ‘The name is Mary.’

Step 1: Start the IDLE Environment for Python. Prior to entering code, save your file by clicking on File and then Save. Select your location and save this file as Lab2-4.py. Be sure to include the .py extension.

Step 2: Document the first few lines of your program to include your name, the date, and a brief description of what the program does. Description of the program should be: # This program determines if a bonus and an extra day off # will be awarded.

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Step 3: Start your program with the following code: # This program determines if a bonus and an extra day off # will be awarded # Get the monthly sales monthlySales = float(input('Enter the monthly sales $')) Step 4: Add code that determines whether a bonus is awarded. Your code might look as follows. Note that the if statement is followed by a colon, and the print statement inside must be tabbed over. # Determine if there is a bonus. if monthlySales >= 100000: print("You have earned a $5,000 bonus!!!")

Step 5: Add code that determines whether the employees get an extra day off. Your code might look as follows. Note that the if statement is followed by a colon, and the print statement inside must be tabbed over. # Determine if employees get an extra day off. if monthlySales >= 112500: print("All employees get a day off!!!")

Step 6: Click Run and Run Module to see how your program processes. Test the following monthlySales values to verify the expected output.

Monthly Sales monthlySales = 102500 monthlySales = 90000 monthlySales= 112500

Expected Output You earned a $5000 bonus! <nothing> You earned a $5000 bonus!

All employees get one day off!!!

Step 9: Execute your program so that it works and paste the final code below PASTE CODE HERE

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Lab 2.5 – Programming Challenge 1 – Guess the Secrets Write the Pseudocode, Flowchart, and Python code for the following programming problem.

Guess the Secrets Write a program that will ask the user to guess a person’s age, their height in inches, and their birth month. Your program will compare the entered values to the following and display the appropriate responses.

The Secret Answers age = 25 height = 72 birthMonth = "April"

The Comparison If the guessed age is less than or equal to 25 If the guessed height is greater than or equal to 72 If the guessed birth month is equal to April

The Printed Response Congratulations, the age is 25 or less Congratulations, the height is 72 or more Congratulations, the birth month is April

Hint: This program can be written a few different ways. It is suggested that only three variables are used to store the guessed answers to age, height, and birthMonth. The following shows the partially-written pseudocode: // Declare variables Declare Integer age Declare Integer height Declare String birthMonth // Get the user's guess for age.

Display "Enter your guess for age: " Input age // Get the user's guess for height.

Display "Enter your guess for height in inches: " Input height // Get the user's guess for birth month.

Display "Enter your guess for birth month: " Input birthMonth // Determine if the age is correct and display the results. // Write your pseudocode here: // Determine if the height is correct and display the results. // Write your pseudocode here: // Determine if the birth month is correct and display the results. // Write your pseudocode here:

Starting Out with Programming Logic and Design If the program is written properly, sample output should look as follows: Sample 1: //Input Enter your guess for age: 20 Enter your guess for height: 74 Enter your guess for birth month: March //Output Congratulations, the age is 25 or less.

Congratulations, the height is 72 or more.

Sample 2: //Input Enter your guess for age: 32 Enter your guess for height: 68 Enter your guess for birth month: April //Output Congratulations, the birth month is April.

Sample 3: //Input Enter your guess for age: 58 Enter your guess for height: 72 Enter your guess for birth month: January //Output Congratulations, the height is 72 or more.

The Pseudocode TYPE PSEUDOCODE HERE The Flowchart PASTE FLOWCHART HERE The Python Code PASTE CODE HERE

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Python Instructor Manual

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Python Instructor Manual Lab 3: Decisions and Boolean Logic The if-else Statement In code we write a dual alternative decision structure as an if-else statement. Here is the general format of the if-else statement: if condition: statement statement etc. else: statement statement etc.

Here is a practical example: if temperature < 40: print("A little cold, isn't it?") else: print("Nice weather we're having.")

When you write an if-else statement, follow these guidelines for indentation: • •

Make sure the if clause and the else clause are aligned.

The if clause and the else clause are each followed by a block of statements.

Make sure the statements in the blocks are consistently indented.

The if-elif-else Statement While nested if-else statements are allowed, this lab steers students toward the use of if-elif-else statements, as they are easier to follow. Here is the general format of the if-elif-else statement: if condition_1: statement statement etc. elif condition_2: statement statement etc.

Python Instructor Manual

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Insert as many elif clauses as necessary… else: statement statement etc.

Here is a practical example: if score < 60: print('Your grade is F.') elif score < 70: print('Your grade is D.') elif score < 80: print('Your grade is C.') elif score < 90: print('Your grade is B.') else: print('Your grade is A.') Logical Operators Python provides a set of operators known as logical operators, which you can use to create complex Boolean expressions.

Operator and

Meaning The and operator connects two Boolean expressions into one compound expression. Both subexpressions must be true for the compound expression to be true.

or

The or operator connects two Boolean expressions into one compound expression. One or both subexpressions must be true for the compound expression to be true. It is only necessary for one of the subexpressions to be true, and it does not matter which.

not

The not operator is a unary operator, meaning it works with only one operand. The operand must be a Boolean expression. The not operator reverses the truth of its operand. If it is applied to an expression that is true, the operator returns false. If it is applied to an expression that is false, the operator returns true.

Here is a practical example of the and operator: if temperature < 20 and minutes > 12: print('The temperature is in the danger zone.')

Python Instructor Manual

Here is a practical example of the or operator: if temperature < 20 or temperature > 100: print('The temperature is in the danger zone.')

Here is a practical example of the not operator: if not(temperature > 100): print('This is below the maximum temperature.')

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Solutions Lab 3: Decisions and Boolean Logic Note to Instructor: This lab accompanies Chapter 4 of Starting Out with Programming Logic & Design, with a focus on nested If-Then-Else statements and logical operators. Material in the chapter should have been covered prior to lab assignment.

Evaluation: The instructor should be present to answer any questions and observe the student performing the lab. The student should turn in a hard copy (paper) or soft copy (email) of their work.

Learning Objectives for this lab include: 1. Understand how logical operators function.

2. Understand how Boolean expressions process.

3. Learn how to write a nested If-Then-Else statement in pseudocode, flowcharts, and Python code.

Lab 3.1 walks the student through the process of using Logical Operators and Dual Alternative Decisions.

Lab 3.2 uses the following programming problem.

A triangle has three angles, and the sum of the three angles is always 180. Write a program that asks the user to enter a triangle's three angles and displays a message indicating whether the triangle is valid or not.

Labs 3.3, 3.4, and 3.5 uses the following programming problem.

When you visit a website, your browser sends a request to the web server, and the web server sends a response code back to your browser. The response code indicates whether the web server can fulfill the request. There are many response codes, but here are five common codes with their meanings: • • • • •

200 – OK 401 – Unauthorized 403 – Forbidden 404 – Not Found 408 – Request Timeout

Write a program that prompts the user to enter one of the response codes shown above, and then displays the meaning of the response code. If the user enters anything other than one of the codes shown above, the program should display "Unknown Code". Use an If-Then-Else-If statement in your pseudocode.

Starting Out with Programming Logic and Design

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Lab 3.6 uses the following programming problem.

Write the Pseudocode, Flowchart, and Python code for the following programming problem.

Write a program that will calculate a XXX% tip and a 6% tax on a meal price. The user will enter the meal price and the program will calculate tip, tax, and the total. The total is the meal price plus the tip plus the tax. Your program will then display the values of tip, tax, and total.

The restaurant wants the tip percentage to be based on the meal price. The amounts are as follows: Meal Price Range .01 to 5.99 6 to 12.00 12.01 to 17.00 17.01 to 25.00 25.01 and more

Tip Percent 10% 13% 16% 19% 22%

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Lab 3.1 –Logical Operators and Dual Alternative Decisions Step 1: Consider the following values set to variables.

• myAge = 32 • yourAge = 18 • myNumber = 81 • yourNumber = 17 • votingAge = 18 Step 2: Based on the values to the variables in Step 1, what is the expected output?

Hint: The output will be either what is printed to the screen, or nothing.

The condition If myAge == 31 AND yourAge < myAge Then Display "My age is 31 and your age is less than that" End If If myAge <= 35 AND myAge >= 32 Then Display "My age is between 32 and 35" End If If yourAge == votingAge OR yourAge > votingAge Then Display "You can vote" End If If myNumber == 83 OR yourNumber == 83 Then Display "One of our numbers is 83" End If

Expected Output Nothing My age is between 32 and 35 You can vote Nothing

Step 3: Based on the values to the variables in Step 1, what is the expected output?

The condition If myAge == 31 AND yourAge < myAge Then Display "My age is 31 and your age is less than that" Else Display "Our ages do not qualify" End If If myAge <= 35 AND myAge >= 32 Then Display "My age is between 32 and 35" Else Display "My age is not within that range" End If If yourAge == votingAge OR yourAge > votingAge Then Display "You can vote" Else Display "You cannot vote" End If If myNumber == 83 OR yourNumber == 83 Then Display "One of our numbers is 83" Else Display "83 is not our numbers" End If

Expected Output Our ages do not qualify My age is between 32 and 35 You can vote

83 is not our numbers

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Lab 3.2 – Pseudocode: Dual Alternative Decisions Step 1: Declare the necessary variables.

• Declare an Integer variable named angle1 to hold the value of the first angle.

• Declare an Integer variable named angle2 to hold the value of the second angle.

• Declare an Integer variable named angle3 to hold the value of the third angle.

• Declare an Integer variable named sum to hold the sum of the angles.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum Step 2: Prompt the user to enter the first angle. Assign the input to the angle1 variable.

Display "Enter angle 1."

Input angle1 Step 3: Prompt the user to enter the second angle. Assign the input to the angle2 variable.

Display "Enter angle 2."

Input angle2 Step 4: Prompt the user to enter the third angle. Assign the input to the angle3 variable.

Display "Enter angle 3."

Input angle3 Step 5: Calculate the sum of the three angles and assign the result to the sum variable.

Set sum = angle1 + angle2 + angle3 Step 6: Write an If-Else statement that determines whether the sum is equal to 180. If so, display the message "The triangle is valid." Otherwise display the message "That is not a valid triangle."

If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

End If

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Lab 3.3 – Pseudocode: Nested Decision Structures Step 1: Declare an Integer variable named code. This variable will hold the user's input.

Declare Integer code Step 2: Write statements that prompt the user to enter a response code, and then assign the user's input to the code variable.

Display "Enter a response code."

Input code Step 3: Complete the following If-Then-Else-If statement to display the meaning of the code: If code == 200 Then Display "OK" Else If code == 401 Then Display "Unauthorized" Else If code == 403 Then Display "Forbidden" Else If code == 404 Then Display "Not Found" Else If code == 408 Then Display "Request Timeout" Else Display "Unknown code" End If

Starting Out with Programming Logic and Design

Lab 3.4 – Flowcharts Note to instructor: Steps 1 – 4 walk students through the process of designing flowcharts. Step 5 requires them to include their completed flowchart.

Step 5: The final step is to insert your finished flowchart in the space below. Inside Raptor, select File and the Print to Clipboard from the menu. Inside Word in the space below, select Edit and Paste.

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Lab 3.5 – Python Code Note to instructor: Steps 1 – 5 walk students through the process of writing the Python code. Step 6 requires them to copy and paste their final Python code into the document.

Here is an example of the final code: # Lab 3-5 code = int(input("Enter a response code: ")) if code == 200: print("OK") elif code == 401: print("Unauthorized") elif code == 403: print("Forbidden") elif code == 404: print("Not Found") elif code == 408: print("Request Timeout") else: print("Unknown code")

Starting Out with Programming Logic and Design

Lab 3.6 – Programming Challenge 1 – Tip, Tax, and Total The Pseudocode // Declare local variables Declare Real mealprice Declare Real tip Declare Real tax Declare Real total // Get the meal price.

Display "Enter the meal price $" Input mealprice // Calculate the tip.

If mealprice >= .01 AND mealprice <= 5.99 Then Set tip = mealprice * .10 Else If mealprice >= 6 AND mealprice <= 12 Then Set tip = mealprice * .13 Else If mealprice >= 12.01 AND mealprice <= 17 Then Set tip = mealprice * .16 Else If mealprice >= 17.01 and mealprice <= 25 Then Set tip = mealprice * .19 Else tip = mealprice * .22 End If // Calculate the tax.

Set tax = mealprice * .06 // Calculate the total.

Set total = mealprice + tip + tax // Display the results.

Display "The meal price is $", mealprice Display "The tip is $", tip Display "The tax is $", tax Display "The total is $", total

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Starting Out with Programming Logic and Design The Flowchart

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Starting Out with Programming Logic and Design The Python Code # Lab 3-6 print('Welcome to the tip and tax calculator program') print() #prints a blank line # Get the meal price. mealprice = float(input('Enter the meal price $')) # Calculate the tip. if mealprice >= .01 and mealprice <= 5.99: tip = mealprice * .10 elif mealprice >= 6 and mealprice <=12: tip = mealprice * .13 elif mealprice >=12.01 and mealprice <=17: tip = mealprice * .16 elif mealprice >= 17.01 and mealprice <=25: tip = mealprice * .19 else: tip = mealprice * .22 # Calculate the tax. tax = mealprice * .06 # Calculate the total. total = mealprice + tip + tax # Display the results. print('The meal price is $', mealprice) print('The tip is $', tip) print('The tax is $', tax) print('The total is $', total)

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Starting Out with Programming Logic and Design

Lab 3: Decisions and Boolean Logic This lab accompanies Chapter 3 of Starting Out with Programming Logic & Design.

Name:

Lab 3.1 –Logical Operators and Dual Alternative Decisions Critical Review The logical AND operator and the logical OR operator allow you to connect multiple Boolean expressions to create a compound expression.

The logical NOT operator reverses the truth of a Boolean expression.

When using the AND operator, both conditions must be true in order for the statements within an if to process.

When using the OR operator, either condition must be true in order for the statements within an if to process.

A dual alternative decision structure will execute one group of statements if its Boolean expression is true, or another group if its Boolean expression is false.

The general structure of an if-then-else statement is If condition Then Statement Statement Etc. Else Statement Statement Etc. End If

This lab requires you to think about possible true and false conditions using if statements.

Step 1: Consider the following values set to variables.

• myAge = 32 • yourAge = 18 • myNumber = 81 • yourNumber = 17 • votingAge = 18

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Step 2: Based on the values to the variables in Step 1, what is the expected output?

Hint: The output will be either what is printed to the screen, or nothing. (Reference: Logical Operators, Chapter 3).

The condition

Expected Output

If myAge == 31 AND yourAge < myAge Then Display "My age is 31 and your age is less than that" End If

If myAge <= 35 AND myAge >= 32 Then Display "My age is between 32 and 35" End If If yourAge == votingAge OR yourAge > votingAge Then Display "You can vote" End If If myNumber == 83 OR yourNumber == 83 Then Display "One of our numbers is 83" End If

Step 3: Based on the values to the variables in Step 1, what is the expected output?

(Reference: Dual Alternative Decision Structures, Chapter 3).

The condition If myAge == 31 AND yourAge < myAge Then Display "My age is 31 and your age is less than that" Else Display "Our ages do not qualify" End If If myAge <= 35 AND myAge >= 32 Then Display "My age is between 32 and 35" Else Display "My age is not within that range" End If If yourAge == votingAge OR yourAge > votingAge Then Display "You can vote" Else Display "You cannot vote" End If If myNumber == 83 OR yourNumber == 83 Then Display "One of our numbers is 83" Else Display "83 is not our numbers" End If

Expected Output

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Lab 3.2 – Pseudocode: Dual Alternative Decisions Critical Review A dual alternative decision structure will execute one group of statements if its Boolean expression is true, or another group if its Boolean expression is false.

The general structure of an if-then-else statement is: If condition Then Statement Statement Etc. Else Statement Statement Etc. End If Module Review Recall the difference between a reference variable and a value variable. Reference variables are used in the following lab when the value of the variable is modified in the module. You’ll notice some parameter lists include the keyword Ref before the variable that is going to change within the module.

This lab requires you to think about the steps that take place in a program by writing algorithms. Read the following instructions prior to completing the lab.

A triangle has three angles, and the sum of the three angles is always 180. Write a program that asks the user to enter a triangle's three angles and displays a message indicating whether the triangle is valid or not.

Step 1: Declare the necessary variables.

• Declare an Integer variable named angle1 to hold the value of the first angle.

• Declare an Integer variable named angle2 to hold the value of the second angle.

• Declare an Integer variable named angle3 to hold the value of the third angle.

• Declare an Integer variable named sum to hold the sum of the angles.

Step 2: Prompt the user to enter the first angle. Assign the input to the angle1 variable.

Step 3: Prompt the user to enter the second angle. Assign the input to the angle2 variable.

Starting Out with Programming Logic and Design Step 4: Prompt the user to enter the third angle. Assign the input to the angle3 variable.

Step 5: Calculate the sum of the three angles and assign the result to the sum variable.

Step 6: Write an If-Else statement that determines whether the sum is equal to 180. If so, display the message "The triangle is valid." Otherwise display the message "That is not a valid triangle."

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Lab 3.3 – Pseudocode: Nested Decision Structures Critical Review To test more than one condition, a decision structure can be nested inside another decision structure. This structure can become very complex, and often an If-Then-Else-If statement is used instead.

The general structure of the If-Then-Else-If statement is: If condition_1 Then Statement Statement Etc. Else If condition_2 Then Statement Statement Etc. Insert as many Else If clauses as necessary Else Statement Statement Etc. End If

A case structure lets the value of a variable or an expression determine which path of execution the program will take. This is often used as an alternative to a nested if else decision.

This lab requires you to think about the steps that take place in a program by writing algorithms. Read the following instructions prior to completing the lab.

When you visit a website, your browser sends a request to the web server, and the web server sends a response code back to your browser. The response code indicates whether the web server can fulfill the request. There are many response codes, but here are five common codes with their meanings: • • • • •

200 – OK 401 – Unauthorized 403 – Forbidden 404 – Not Found 408 – Request Timeout

Write a program that prompts the user to enter one of the response codes shown above, and then displays the meaning of the response code. If the user enters anything other than one of the codes shown above, the program should

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display "Unknown Code". Use an If-Then-Else-If statement in your pseudocode.

Step 1: Declare an Integer variable named code. This variable will hold the user's input.

Step 2: Write statements that prompt the user to enter a response code, and then assign the user's input to the code variable.

Step 3: Complete the following If-Then-Else-If statement to display the meaning of the code: If code == Display Else If code == Display Else If code == Display Else If code == Display Else If code == Display Else Display End If

Then Then Then Then Then

Starting Out with Programming Logic and Design

Lab 3.4 – Flowcharts Critical Review A dual alternative decision structure has two possible paths of execution – one path is taken if a condition is true, and the other path is taken if the condition is false.

A diamond with a true and false value is used in flowcharting a dual alternative decision structure.

Nested if-then-else flowcharts look as follows:

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Starting Out with Programming Logic and Design This lab requires you to convert your pseudocode in Lab 3.3 to a flowchart. Use an application such as Raptor, Flowgorithm, or Visio.

Step 1: Start Raptor and save your document as Lab 3-4. The .rap file extension will be added automatically. Start by adding a Comment box that declares your variables.

Step 2: The next step in your flowchart should be to prompt the user to enter a response code, and assign the input to the code variable. Your flowchart should appear as follows:

Step 3: Next, add the nested decision structures that perform as the If-Then-Else statement from Lab 3.3, Step 3. Do not forget the final else which executes when the user enters an unknown value. Your flowchart should appear as follows:

Step 4: When your program is complete, test the following input values to ensure that the output is correct. If your output is different, then review your code.

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Input Values 200 401 403 404 408 Any other value

Expected Output OK Unauthorized Forbidden Not Found Request Timeout Unknown code

Step 5: The final step is to insert your finished flowchart in the space below. Inside Raptor, select File and the Print to Clipboard from the menu. Inside Word in the space below, select Edit and Paste.

PASTE FLOWCHART HERE

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Lab 3.5 – Python Code Critical Review In code we write a dual alternative decision structure as an if-else statement. Here is the general format of the if-else statement: if condition: statement statement etc. else: statement statement etc.

Here is the general format of the if-elif-else statement: if condition_1: statement statement etc. elif condition_2: statement statement etc.

Insert as many elif clauses as necessary… else: statement statement etc.

The logical operators and, or, and not are used in Python to connect Boolean expressions.

Step 1: Start the IDLE Environment for Python. Prior to entering code, save your file by clicking on File and then Save. Select your location and save this file as Lab3-5.py. Be sure to include the .py extension.

Step 2: Document the first few lines of your program to include your name, the date, and a brief description of what the program does.

Step 3: Add the following code to prompt the user to enter a response code:

Starting Out with Programming Logic and Design

code = int(input("Enter a response code: "))

Step 4: Add the following if-elif-else statement to determine the meaning of the response code entered by the user: if code == 200: print("OK") elif code == 401: print("Unauthorized") elif code == 403: print("Forbidden") elif code == 404: print("Not Found") elif code == 408: print("Request Timeout") else: print("Unknown code")

Step 5: Click Run and Run Module to see how your program processes. Test the following values to verify the expected output.

Input Values 200 401 403 404 408 Any other value

Expected Output OK Unauthorized Forbidden Not Found Request Timeout Unknown code

Step 6: Copy and paste your final code below PASTE CODE HERE

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Lab 3.6 – Programming Challenge 1 – Tip, Tax, and Total Write the Pseudocode, Flowchart, and Python code for the following programming problem.

Write a program that will calculate a XXX% tip and a 6% tax on a meal price. The user will enter the meal price and the program will calculate tip, tax, and the total. The total is the meal price plus the tip plus the tax. Your program will then display the values of tip, tax, and total.

The restaurant wants the tip percentage to be based on the meal price. The amounts are as follows: Meal Price Range .01 to 5.99 6 to 12.00 12.01 to 17.00 17.01 to 25.00 25.01 and more

The Pseudocode TYPE PSEUDOCODE HERE The Flowchart PASTE FLOWCHART HERE The Python Code PASTE CODE HERE

Tip Percent 10% 13% 16% 19% 22%

Python Instructor Manual

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Python Instructor Manual Lab 4: Repetition Structures The While Statement Here is the general format of the while loop in Python: while condition: statement statement etc.

Note the colon after the condition. Conditions are written the same as with if statements.

There is no Do While loop in Python.

Since while loops are pretest loops, it is important to always initialize the loop control variable so that it is true on the first iteration.

Here is a practical example: 1 # This program calculates sales commissions.

2 # Create a variable to control the loop.

3 keep_going = 'y' 4 5 # Calculate a series of commissions.

6 while keep_going == 'y': 7 # Get a salesperson's sales and commission rate.

8 sales = float(input('Enter the amount of sales: ')) 9 comm_rate = float(input('Enter the commission rate: ')) 10 11 # Calculate the commission.

12 commission = sales * comm_rate 13 14 # Display the commission.

15 print('The commission is $', commission) 16 17 # See if the user wants to do another one.

18 keep_going = input('Do you want to calculate another ' + 19 'commission (Enter y for yes): ')

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Solutions Lab 4: Repetition Structures Note to Instructor: This lab accompanies Chapter 4 of Starting Out with Programming Logic & Design, with a focus on While and Do-While. Material in the chapter should have been covered prior to lab assignment.

Evaluation: The instructor should be present to answer any questions and observe the student performing the lab. The student should turn in a hard copy (paper) or soft copy (email) of their work.

Learning Objectives for this lab include: 1. Understand how condition and count controlled loops operate.

2. Understand the while and the do-while structure.

3. Learn how to write loops in pseudocode, flowcharts, and Python code.

Lab 4.1 uses the Triangle program from Lab 4.2.

Labs 4.2, 4.3, and 4.4 use the following programming problem: Write a program that will allow a grocery store to keep track of the total number of bottles collected for one week. The program should have a loop that iterates seven times, once for each day in the week. During each iteration, the user enters the number of bottles returned for a particular day.

The program will calculate the total number of bottles returned for the week and the amount paid out (the total returned times .10 cents). The output of the program should include the total number of bottles returned and the total paid out.

Starting Out with Programming Logic and Design

Lab 4.1 –Repetition Structures Pseudocode: Condition Controlled Loops Step 1: Examine the following program from Lab 3.2. In this lab we will modify the program by adding a loop that repeats the process as many times as the user wishes.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum Display "Enter angle 1."

Input angle1 Display "Enter angle 2."

Input angle2 Display "Enter angle 3."

Input angle3 Set sum = angle1 + angle2 + angle3 If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

End If Step 2: In the space provided, add the following modifications: • Declare a loop control variable named keepGoing of the data type String.

Initialize this variable to "y".

• Complete the While statement.

• Complete the Input statement.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum Declare String keepGoing = "y" While keepGoing = "y" Display "Enter angle 1."

Input angle1 Display "Enter angle 2."

Input angle2 Display "Enter angle 3."

Input angle3 Set sum = angle1 + angle2 + angle3

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If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

End If Display "Do you want to run the program again? (y/n)" Input keepGoing End While Step 3: Now you will modify the original program to use a Do-While loop. In the space provided, add the following modifications: • Declare a loop control variable named keepGoing of the data type String.

Initialize this variable to "y".

• Complete the Input statement.

• Complete the While statement.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum Declare String keepGoing = "y" Do Display "Enter angle 1."

Input angle1 Display "Enter angle 2."

Input angle2 Display "Enter angle 3."

Input angle3 Set sum = angle1 + angle2 + angle3 If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

End If Display "Do you want to run the program again? (y/n)" Input keepGoing While keepGoing = "y"

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Lab 4.2 –Repetition Structures Pseudocode: Counter Controlled Loops Step 1: In the pseudocode below, declare the following variables: • In line 2, declare a variable called totalBottles that is initialized to 0.

This variable will store the accumulated bottle values • In line 3, declare a variable called counter and that is initialized to 1. This variable will control the loop • In line 4, declare a variable called todayBottles that is initialized to 0.

This variable will store the number of bottles returned on a day • In line 5, declare a variable called totalPayout that is initialized to 0. This variable will store the calculated value of totalBottles times .10 1 // Step 1: Declare variables below 2 Declare Integer totalBottles = 0 3 Declare Integer counter = 1 4 Declare Integer todayBottles = 0 5 Declare Real totalPayout 6 7 // Step 2: Complete the While loop 8 While counter <= 7 9 Display "Enter number of bottles returned for the day:" 10 Input todayBottles 11 Set totalBottles = totalBottles + todayBottles 12 // Step 3: Add 1 to counter.

13 Set counter = counter + 1 14 End While 15 16 Set totalPayout = totalBottles * .10 17 Display "The total number of bottles returned was ", 18 totalBottles 19 Display "The total payout for bottles is $", totalPayout

Step 2: In line 8 of the pseudocode above, complete the While loop. The loop should iterate as long as counter is less-than-or-equal-to 7.

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Lab 4.3 – Flowcharts Note to instructor: Steps 1 – 14 walk students through the process of designing flowcharts. Steps 16 and 17 lead the student through debugging the flowchart in Raptor.

Step 18 requires students to paste their final flowchart. The final flow chart is below:

Lab 4.4 – Python Code

Starting Out with Programming Logic and Design

Note to instructor: Steps 1 – 17 walk students through the process of writing the program. Step 18 requires them to include their completed code, which is shown here: # Lab 4-4 The Bottle Return Program counter = 1 totalBottles = 0 todayBottles = 0 totalPayout = 0 while counter <= 7: todayBottles = int(input('Enter number of bottles for today: ')) totalBottles = totalBottles + todayBottles counter = counter + 1 totalPayout = totalBottles * .10 print('The total number of bottles collected is', totalBottles) print('The total paid out is $', totalPayout)

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Lab 4: Repetition Structures This lab accompanies Chapter 5 of Starting Out with Programming Logic & Design.

Name:

Lab 4.1 –Repetition Structures Pseudocode: Condition Controlled Loops Critical Review A repetition structure causes a statement or set of statements to execute repeatedly.

Repetition structures are used to perform the same task over and over.

Repetition structures are commonly called loops A condition-controlled loop uses a true/false condition to control the number of times that it repeats.

The general structure of a While loop with a condition-controlled statement is: //Declare loop control variable While condition Statement Statement Etc. //Ask Question that changes the loop control variable End While The general structure of a Do While loop with a condition-controlled statement is: //Declare loop control variable Do Statement Statement Etc. //Ask Question that changes the loop control variable While Condition

This lab requires you to implement a condition controlled loop.

Starting Out with Programming Logic and Design Step 1: Examine the following program from Lab 3.2. In this lab we will modify the program by adding a loop that repeats the process as many times as the user wishes.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum Display "Enter angle 1."

Input angle1 Display "Enter angle 2."

Input angle2 Display "Enter angle 3."

Input angle3 Set sum = angle1 + angle2 + angle3 If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

End If Step 2: In the space provided, add the following modifications: • Declare a loop control variable named keepGoing of the data type String.

Initialize this variable to "y".

• Complete the While statement.

• Complete the Input statement.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum While Display "Enter angle 1."

Input angle1 Display "Enter angle 2."

Input angle2 Display "Enter angle 3."

Input angle3 Set sum = angle1 + angle2 + angle3 If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

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End If Display "Do you want to run the program again? (y/n)" Input End While Step 3: Now you will modify the original program to use a Do-While loop. In the space provided, add the following modifications: • Declare a loop control variable named keepGoing of the data type String.

Initialize this variable to "y".

• Complete the Input statement.

• Complete the While statement.

Declare Integer angle1 Declare Integer angle1 Declare Integer angle1 Declare Integer sum Do Display "Enter angle 1."

Input angle1 Display "Enter angle 2."

Input angle2 Display "Enter angle 3."

Input angle3 Set sum = angle1 + angle2 + angle3 If sum == 180 Then Display "The triangle is valid."

Else Display "That is not a valid triangle."

End If Display "Do you want to run the program again? (y/n)" Input While

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Lab 4.2 –Repetition Structures Pseudocode: Counter Controlled Loops Critical Review A count-controlled loop repeats a specific number of times.

The loop keeps a count of the number of times that it iterates, and when the count reaches a specified amount the loop stops.

A variable, known as a counter variable, is used to store the number of iterations that it has performed.

The three actions that take place are initialization, test, and increment.

• Initialization: Before the loop begins, the counter variable is initialized to a starting value.

• Test: The loop tests the counter variable by comparing it to a maximum value.

• Increment: To increment a variable means to increase its value. This is done by adding one to the loop control variable.

Any loop can be used with a count-controlled loop.

A running total is a sum of numbers that accumulates with each iteration of a loop. The variable used to keep the running total is called an accumulator.

This lab requires you to complete a program using a condition controlled loop, a counter controlled loop, and an accumulator. The program is as follows: Write a program that will allow a grocery store to keep track of the total number of bottles collected for one week. The program should have a loop that iterates seven times, once for each day in the week. During each iteration, the user enters the number of bottles returned for a particular day.

The program will calculate the total number of bottles returned for the week and the amount paid out (the total returned times .10 cents). The output of the program should include the total number of bottles returned and the total paid out.

Step 1: In the pseudocode below, declare the following variables: • In line 2, declare a variable called totalBottles that is initialized to 0.

This variable will store the accumulated bottle values • In line 3, declare a variable called counter and that is initialized to 1. This variable will control the loop • In line 4, declare a variable called todayBottles that is initialized to 0.

This variable will store the number of bottles returned on a day

Starting Out with Programming Logic and Design •

In line 5, declare a variable called totalPayout that is initialized to 0. This variable will store the calculated value of totalBottles times .10

1 // Step 1: Declare variables below 2 3 4 5 6 7 // Step 2: Complete the While loop 8 While 9 Display "Enter number of bottles returned for the day:" 10 Input todayBottles 11 Set totalBottles = totalBottles + todayBottles 12 // Step 3: Add 1 to counter.

13 14 End While 15 16 Set totalPayout = totalBottles * .10 17 Display "The total number of bottles returned was ", 18 totalBottles 19 Display "The total payout for bottles is $", totalPayout

Step 2: In line 8 of the pseudocode above, complete the While loop. The loop should iterate as long as counter is less-than-or-equal-to 7.

Step 3: In line 13 of the pseudocode above, write a statement that adds 1 to the counter variable..

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Lab 4.3 – Flowcharts Critical Review In a While loop, the question is asked first. After the statements process, the control goes back above the condition.

Condition

True

Statements

False

In a Do-While loop, the question is asked last. The statements always process at least one time.

Statements

True

Condition

False

This lab requires you to convert your pseudocode in Lab 4.2 to a flowchart. Use an application such as Raptor or Visio.

Step 1: Start Raptor and save your document as Lab 4-3. The .rap file extension will be added automatically. Start by adding a Comment box that declares your variables.

Step 2: Click the Loop symbol and drag and drop it between the Start and the End symbol.

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Step 3: Double click the Diamond symbol, and type counter > 7 as the condition.

Note that in Raptor, all loops work like a Do-Until loop. For this reason, we must specify the condition that will cause the loop to stop iterating.

Step 4: Click the Input symbol and drag and drop it between the Loop symbol and the Diamond symbol.

Step 5: Double click the Input symbol and ask the question "Enter the number of bottles returned for the day:". Store the input in the todaybottles variable.

Step 6: Click the Assignment symbol and drag and drop it between the Input symbol and the Diamond symbol.

Step 7: Double click the Assignment symbol. Complete the assignment operation so it sets the totalBottles variable to totalBottles + todayBottles.

Step 8: Create another Assignment symbol, immediately after the one you just created.

This Assignment operation should sets the counter variable to counter + 1. At this point, your flowchart should appear as follows:

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Step 9: Click the Assignment symbol and drag and drop it immediately after the Diamond symbol.

Step 10: Double click the Assignment symbol. Complete the assignment operation so it sets the totalPayout variable to totalBottles * .10.

Step 11: Click the Output symbol and drag and drop it immediately after the Assignment symbol that you created in Step 10.

Step 12: Double click the Output symbol that you just created. Complete the operation so it displays "The total number of bottles returned was " + totalBottles.

Step 13: Click the Output symbol and drag and drop it immediately after the Output symbol that you created in steps 11 and 12.

Step 14: Double click the Output symbol that you just created. Complete the operation so it displays "The total payout for bottles is $" + totalPayout.

Now your flowchart should look as the following:

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Step 15: Save your program and try running it. You'll notice an error occur when the loop starts processing. This is because totalBottles was never initialized, even though we added a comment with our variable declarations. The comment is for us to see, but it does not actually create the variables.

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Step 16: To fix the error, add three Assignment symbols above the Loop symbol. In one symbol, set counter to 1. In the other, set totalBottles to 0. In the other, set todayBottles to 0. Your flowchart should look as follows:

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Step 17: Test your program against the following values. If there is an error, go back through the steps to locate the problem.

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Input Values Seven days of bottles: 346 238 638 890 1035 899 536

Expected Output The total number of bottles collected were: 4582 The total amount paid out is $458.2000

Step 18: The final step is to insert your finished flowchart in the space below.

PASTE FLOWCHART HERE

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Lab 4.4 – Python Code Critical Review In Python, you use the while statement to write a condition-controlled loop. The loop has two parts: (1) a condition that is tested for a true or false value, and (2) a

statement or set of statements that is repeated as long as the condition is true.

A while loop can also be used for count-controlled loops.

Here is the general format of the while loop in Python: while condition: statement statement etc.

Since the while loop is a pre-test, it is important to initialize your loop control variable to a starting value so that the first iteration will be true.

As with all loops, be sure to change the loop control variable either by incrementing or asking a question.

The goal of this lab is to convert the Bottle Return program to Python code.

Step 1: Start the IDLE Environment for Python. Prior to entering code, save your file by clicking on File and then Save. Select your location and save this file as Lab4-4.py. Be sure to include the .py extension.

Step 2: Document the first few lines of your program to include your name, the date, and a brief description of what the program does.

Step 3: Write statements that initialize your variables to starting values. In Python and most programming languages, in order for variables to be used, they need to have a starting value. Your code should look as follows: counter = 1 totalBottles = 0 todayBottles = 0 totalPayout = 0

Step 4: Write a while loop with the condition of counter <= 7. This code should look as follows: while counter <= 7:

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Step 11: Inside the while loop, write a statement that allows the user to enter the number of bottles for today. This code should look as follows: todayBottles = int(input('Enter number of bottles for today: '))

Step 12: Next, write the accumulator statement. This code should look as follows: totalBottles = totalBottles + todayBottles

Step 13: The last statement inside the loop should increment counter by one so the loop will end after seven iterations. This code should look as follows: counter = counter + 1

Step 14: After the loop, write a statement that calculates the total payout and assigns the result to the totalPayout variable. This statement should look as follows: totalPayout = totalBottles * .10

Step 15: Write a statement that displays the total number of bottles collected. The statement should look as follows: print('The total number of bottles collected is', totalBottles)

Step 16: Write a statement that displays the total amount paid out. The statement should look as follows: print('The total paid out is $', totalPayout)

Step 17: Click Run and Run Module to see how your program processes. Test the following values to verify the expected output. >>> Enter number of bottles for today: 346 Enter number of bottles for today: 238 Enter number of bottles for today: 638 Enter number of bottles for today: 890 Enter number of bottles for today: 1035 Enter number of bottles for today: 899 Enter number of bottles for today: 536 The total number of bottles collected is 4582 The total paid out is $ 458.2 Step 18: Paste the final code below PASTE CODE HERE

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Python Instructor Manual

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Python Instructor Manual Lab 5: Modules Divide and Conquer Lab 5 focuses on breaking up processes into many different modules so students become familiar with the concept of divide and conquer. Large tasks divided into many smaller tasks will help them understand how functions and Python work together.

Naming Functions Python requires that you follow the same rules that you follow when naming variables, which are recapped here: • • • • •

You cannot use one of Python's key words as a function name.

A function name cannot contain spaces.

The first character must be one of the letters a through z, A through Z, or an underscore character (_).

After the first character, you may use the letters a through z or A through Z, the digits 0 through 9, or underscores.

Uppercase and lowercase characters are distinct.

Defining and Calling a Function To create a function, you write its definition. Here is the general format of a function definition in Python: def function_name(): statement statement etc.

A call is then made by a simple statement such as: function_name() Using a Main Function To reinforce the concept of everything centering on a main module, students should be encouraged to always use a main(). The following figure demonstrates the general setup with a main function definition, and a call to main. The main function should control the calls to all other functions within the program.

Python Instructor Manual

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Indentation in Python In Python, each line in a block must be indented. Indentations that are not aligned evenly will cause compiler errors.

Local Variables and Passing Arguments A variable's scope is the part of a program in which the variable may be accessed. A variable is visible only to statements in the variable’s scope. A local variable's scope is the function in which the variable is created.

The following code will print that the value is 10 because the changevalue() cannot see the local value variable. #the main function def main(): value = 10 changevalue() print('The value is ', value) def changevalue(): value = 50 #calls main main() One way to fix this issue is to pass the value to the function and set it equal to the value.

Additionally, a return value statement is added to the function. This is demonstrated in the following code:

Python Instructor Manual # the main function def main(): value = 10 value = changevalue(value) print('The value is ', value) def changevalue(value): value = 50 return value # calls main main() Of course, additional methods could be used to fix this problem. Another solution is to print the value inside of the changevalue() function. However, this will not suffice when the value needs to be passed to other functions later in the program.

Multiple arguments can also be passed to functions simply by separating the values with commas. The arguments and the parameter list must be listed sequentially.

General Flow of Programs for Lab 5 While there are various ways to structure programs, Lab 5 encourages students to create local variables in main and set the function to return the modified value. For example: # the main function def main(): totalsales = inputData() countytax = calcCounty(totalsales) statetax = calcState(totalsales) totaltax = calcTotal(countytax, statetax) printData(countytax, statetax, totaltax) # this function will input meal price def inputData(): totalsales = float(input('Enter the total sales for the month $')) return totalsales # this function will calculate tip at 20% def calcCounty(totalsales): countytax = totalsales * .02 return countytax # this function will calculate tax at 6% def calcState(totalsales): statetax = totalsales * .04 return statetax # this function will calculate tip, tax, and the total cost def calcTotal(countytax, statetax): totaltax = countytax + statetax

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Python Instructor Manual return totaltax # this function will print tip, tax, the mealprice, and the total def printData(countytax, statetax, totaltax): print('The county tax is $', countytax) print('The state tax is $', statetax) print('The total tax is $', totaltax) # calls main main()

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Solutions Lab 5: Modules Note to Instructor: This lab accompanies Chapter 3 of Starting Out with Programming Logic & Design. Material in the chapter should have been covered prior to lab assignment. In addition, students should have had instruction on using a flowcharting application such as Raptor and instruction on using the IDLE environment for Python.

Evaluation: The instructor should be present to answer any questions and observe the student performing the lab. The student should turn in a hard copy (paper) or soft copy (email) of their work. To minimize the number of attachments or individual files created for this lab, space is set aside in the lab for students to insert completed exercises.

Directions are provided to students on copying and pasting.

Learning Objectives for this lab include: 1. Understand how modules work.

2. Know how to define and call a module.

3. Learn how to declare local variables.

4. Learn how to pass arguments to modules.

Labs 5.1, 5.2, 5.3, and 5.7 use the following programming problem.

A retail company must file a monthly sales tax report listing the total sales for the month and the amount of state and county sales tax collected. The state sales tax rate is 4 percent and the county sales tax rate is 2 percent. Write a program that asks the user to enter the total sales for the month. The application should calculate and display the following: • The amount of county sales tax • The amount of state sales tax • The total sales tax (county plus state)

Labs 5.4 and 5.5 walk students through steps so they can become familiar with Python code using modules and variables.

Lab 5.6 uses the following programming problem.

Write a program that will calculate a 20% tip and a 6% tax on a meal price. The user will enter the meal price and the program will calculate tip, tax, and the total. The total is the meal price plus the tip plus the tax.

Starting Out with Programming Logic and Design

Lab 5.1 – Algorithms Step 2: Given a total sales of $27,097, answer the following: What is the calculated state tax? 1083.88 What is the calculated county tax? 541.94 What is the calculated total tax? 1625.82

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Lab 5.2 –Pseudocode and Modules Step 1: This program is most easily solved using just four variables. Declare the variables that you will need in the program, using the proper data type and documenting the purpose.

Variable Name

Purpose

Declare Real totalSales Declare Real countyTax Declare Real stateTax Declare Real totalTax

Stores total sales the user inputs Stores the calculated county tax Stores the calculated state tax Stores the calculated total tax

Step 2: Given the major task involved in this program, what modules might you consider including? Describe the purpose of each module. (Reference: See Defining and Calling a Module, Chapter 5).

Module Name

Purpose

Module inputData() Module calcCounty() Module calcState() Module calcTotal() Module printData()

Allows the user to enter required user input Calculates the county tax at 2% of the monthly sales Calculates the state tax at 4% of the monthly sales Calculates the total tax as state plus county Prints the necessary information

Step 3: Complete the pseudocode by writing the missing lines. (Reference: See Defining and Calling a Module, Chapter 5). Also, when writing your modules and making calls, be sure to pass necessary variables as arguments and accept them as reference parameters if they need to be modified in the module. (Reference: See Passing Arguments by Value and by Reference, Chapter 5).

Module main () // Declare local variables Declare Real totalSales Declare Real countyTax Declare Real stateTax Declare Real totalTax // Function calls Call inputData(totalSales) Call calcCounty(totalSales) Call calcState(totalSales) Call calcTotal(countyTax, stateTax, totalTax) Call printData(countyTax, stateTax, totalTax) End Module // this module takes in the required user input Module inputData(Real Ref totalSales) Display "Enter the total sales for the month."

Input totalSales End Module

Starting Out with Programming Logic and Design // this module calculates county tax // totalSales can be a value parameter because it is not // changed in the module. // countyTax must be a reference parameter because it is // changed in the module Module calcCounty(Real totalSales, Real Ref countyTax) countyTax = totalSales * .02 End Module // this module calculates state tax Module calcState(Real totalSales, Real Ref stateTax) stateTAx = totalSales * .04 End Module // this module calculates total tax Module calcTotal(Real countyTax, Real stateTax, Real Ref totalTax) totalTax = countyTax + stateTax End Module // this module prints the requirements of the program Module printData(Real countyTax, Real stateTax, Real totalTax) Display "The county tax is ", countyTax Display "The state tax is ", stateTax Display "The total tax is ", totalTax End Module

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Lab 5.3 –Flowcharts Note to Instructor: Steps 1 – 6 walk students through the process of using Raptor and designing a flowchart.

Step 7 requires students to show their completed flowchart. Variable names and statements will vary from student to student. Also, the lab can be completed using a different flowcharting application such as Visio. If so, the sample solution below will look a little different, but should still have the same fundamental steps.

Instructors should grade on clear variable names, proper flow of program, the correct calculation, and the right output. Below is a sample solution to the programming problem.

Step 7: Main Module

Starting Out with Programming Logic and Design inputData Module

calcCounty Module

calcState Module

calcTotal Module

printData Module

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Starting Out with Programming Logic and Design

Lab 5.4 – Python Code and Functions Note to Instructor: Steps 1 – 7 in this lab require students to write Python code to create a program. Their final program is required in Step 8.

Step 8: # Student Name # Date # Description: #

This program tests out the different ways to use functions

# The main function def main(): welcome_message() # causes welcome_message to execute goodbye_message() # causes goodbye_message to execute # This function is to welcome people to my program def welcome_message(): print('Welcome to my program using functions') print('My name is Joe Student') def goodbye_message(): print('Goodbye...thank you for using my program') # This is the main function that starts the program in motion main() # calls main

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Starting Out with Programming Logic and Design

Lab 5.5 – Python Code and Variables Note to Instructor: Steps 1 – 7 in this lab require students to write Python code to create a program. Their final program is required in Step 8.

Step 8: # This program uses functions and variables # the main function def main(): print('Welcome to the variable program') print() #prints a blank line name = inputName() age = inputAge() print('Hello', name) print('Your age is', age) # this function inputs name def inputName(): name = input('Enter your name: ') return name # this function inputs age def inputAge(): age = int(input('Enter your age: ')) return age # calls main main()

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Lab 5.6 – Writing a Complete Program Note to Instructor: Steps 1 – 15 in this lab walk students through an entire program. Step 16 requires them to paste their entire program.

Step 16: # This program uses functions and variables # the main function def main(): print('Welcome to the tip and tax calculator program') print() # prints a blank line mealprice = input_meal() tip = calc_tip(mealprice) tax = calc_tax(mealprice) total = calc_total(mealprice, tip, tax) print_info(mealprice, tip, tax, total) # this function will input meal price def input_meal(): mealprice = input('Enter the meal price $') mealprice = float(mealprice) return mealprice # this function will calculate tip at 20% def calc_tip(mealprice): tip = mealprice * .20 return tip # this function will calculate tax at 6% def calc_tax(mealprice): tax = mealprice * .06 return tax # this function will calculate tip, tax, and the total cost def calc_total(mealprice, tip, tax): total = mealprice + tip + tax return total # this function will print tip, tax, the mealprice, and the total def print_info(mealprice, tip, tax, total): print('The meal price is $', mealprice)

Starting Out with Programming Logic and Design print('The tip is $', tip) print('The tax is $', tax) print('The total is $', total) # calls main main()

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