Day 5 : Inheritance

We provide the implementation for a Rectangle class in the editor. Perform the following tasks:

  1. Add an area method to Rectangle's prototype.

  2. Create a Square class that satisfies the following:

    • It is a subclass of Rectangle.

    • It contains a constructor and no other methods.

    • It can use the Rectangle class' area method to print the area of a Square object.

Locked code in the editor tests the class and method implementations and prints the area values to STDOUT.

class Rectangle {
    constructor(w, h) {
        this.w = w;
        this.h = h;
    }
}
// Write code that adds an 'area' method to the Rectangle class' prototype
 Rectangle.prototype.area = function () {
     return this.w*this.h;
 }
 
// Create a Square class that inherits from Rectangle and implement its class constructor
class Square extends Rectangle {
     constructor(s){
         super(s,s); //sets the values of w and h to s
         
     }
 }
 
if (JSON.stringify(Object.getOwnPropertyNames(Square.prototype)) === JSON.stringify([ 'constructor' ])) {
    const rec = new Rectangle(3, 4);
    const sqr = new Square(3);
    
    console.log(rec.area());
    console.log(sqr.area());
} else {
    console.log(-1);
    console.log(-1);
}

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