Day 5 : Inheritance
We provide the implementation for a Rectangle class in the editor. Perform the following tasks:
Add an area method to Rectangle's prototype.
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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