Chapter 2: Sequence
2.07 Effective use of Flowcharts and Pseudocode Due to their universal nature, flowcharts and pseudocode are used extensively in the Cambridge IGCSE and O Level Computer Science syllabus. The aim of this book is to help you to learn how to code effective systems in Python. The following chapters make use of flowcharts and pseudocode to define the logic of systems before moving on to specific Python solutions.
TIP After completing a flowchart or pseudocode, it is a good idea to try and follow it through a step at a time in the same way a computer would in order to identify if you have any missing steps.
Learning how to explain the logic of programs by using these design techniques is important not only in your preparation for examination but also for your preparation in using the languages of the future. Language syntax is likely to change but the need for effective computational thinking will remain.
Summary ●
Programmers make use of three constructs when writing code: ● sequence: the logical order in which code is executed ● selection: branching of code onto different paths based on certain conditions ● iteration: repetition of sections of code.
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Before coding a program, it is crucial to design an appropriate algorithm.
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Flowcharts are graphical representations of the logic of a system. They make use of symbols to represent operations or processes, and lines indicate the sequence of operations.
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Pseudocode describes the logic of a system in a similar way to a programming language but without such strict syntax requirements.
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