Swift
When we run the above program using playground, we get the following result: Instance physics is: solid physics Instance equation is: Hertz Instance physics is: Fluid Dynamics Instance formulae is: Giga Hertz Chemistry topics are: 'solid physics', Hertz Maths topics are: 'Fluid Dynamics', Giga Hertz Chemistry topics are: 'Thermo physics', Decibels Maths topics are: 'Astro Physics', MegaHertz Maths topics are: 'Differential Equations', Cosine Series
Typecasting:Any and Any Object The keyword 'Any' is used to represent an instance which belongs to any type including function types. class Subjects { var physics: String init(physics: String) { self.physics = physics } }
class Chemistry: Subjects { var equations: String init(physics: String, equations: String) { self.equations = equations super.init(physics: physics) } }
class Maths: Subjects { var formulae: String init(physics: String, formulae: String) { self.formulae = formulae 186