'use strict';

class Rect {

constructor(x, y, width, height) {

this.x = x;

this.y = y;

this.width = width;

this.height = height;

}

toString() {

return `[${this.x}, ${this.y}, ${this.width}, ${this.height}]`;

}

}

class Square extends Rect {

constructor(x, y, side) {

super(x, y, side, side);

}

}

const p1 = new Square(10, 20, 50);

console.log(p1);

console.log(p1.toString());

console.log(`${p1}`);