HackerRank Day 5: Inheritance 10 days of javascript solution

In this HackerRank Day 5: Inheritance 10 days of the javascript problem We provide the implementation for a Rectangle class in the editor. 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.

HackerRank Day 5: Inheritance 10 days of javascript problem solution.

class Rectangle {
    constructor(w, h) {
        this.w = w;
        this.h = h;
    }
}

/*
 *  Write code that adds an 'area' method to the Rectangle class' prototype
 */

/*
 * Create a Square class that inherits from Rectangle and implement its class constructor
 */
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);
            this.h = s;
            this.w = 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);
}