Implement Queue using Stacks.js

/*Implement the following operations of a queue using stacks.

push(x) -- Push element x to the back of queue.
pop() -- Removes the element from in front of queue.
peek() -- Get the front element.
empty() -- Return whether the queue is empty.*/

/**
 * Initialize your data structure here.
 */
var MyQueue = function() {
    this.q = []
};

/**
 * Push element x to the back of queue. 
 * @param {number} x
 * @return {void}
 */
MyQueue.prototype.push = function(x) {
    this.q.unshift(x)
};

/**
 * Removes the element from in front of queue and returns that element.
 * @return {number}
 */
MyQueue.prototype.pop = function() {
    return this.q.pop()
};

/**
 * Get the front element.
 * @return {number}
 */
MyQueue.prototype.peek = function() {
    return this.q[this.q.length-1]
};

/**
 * Returns whether the queue is empty.
 * @return {boolean}
 */
MyQueue.prototype.empty = function() {
    return this.q[0] == null
};

/** 
 * Your MyQueue object will be instantiated and called as such:
 * var obj = Object.create(MyQueue).createNew()
 * obj.push(x)
 * var param_2 = obj.pop()
 * var param_3 = obj.peek()
 * var param_4 = obj.empty()
 */