// Array.prototype.first = () => this[0]; // Array.prototype.last = () => this[this.length - 1]; Array.prototype.top = function () { return this[this.length - 1]; } Array.prototype.sum = function () { let value = 0; for (const num of object) { value += num; } return value; } Array.random = function (n, max) { return Array.from({ length: n }, () => Math.trunc(Math.random() * max)); }