Stack, follow an ordered set of LIFO (LIFO) principle.
Queue, is a follow FIFO (FIFO) an ordered set of principles.
In JavaScript, we can easily expand out both data structures through an array of related methods.
Stack of JavaScript code to achieve:
/** * Initialize your data structure here. */ var MyStack = function() { this._data = []; }; /** * Push element x onto stack. * @param {number} x * @return {void} */ MyStack.prototype.push = function(x) { this._data.push(x); }; /** * Removes the element on top of the stack and returns that element. * @return {number} */ MyStack.prototype.pop = function() { return this._data.pop(); }; /** * Get the top element. * @return {number} */ MyStack.prototype.top = function() { return this._data[this._data.length -1]; }; /** * Returns whether the stack is empty. * @return {boolean} */ MyStack.prototype.empty = function() { return this._data.length === 0; }; /** * Your MyStack object will be instantiated and called as such: * var obj = new MyStack() * obj.push(x) * var param_2 = obj.pop() * var param_3 = obj.top() * var param_4 = obj.empty() */
Queue JavaScript code to achieve:
/** * Initialize your data structure here. */ var MyQueue = function() { this._queue = []; }; /** * Push element x to the back of queue. * @param {number} x * @return {void} */ MyQueue.prototype.push = function(x) { this._queue.push(x); }; /** * Removes the element from in front of queue and returns that element. * @return {number} */ MyQueue.prototype.pop = function() { return this._queue.shift(); }; /** * Get the front element. * @return {number} */ MyQueue.prototype.peek = function() { return this._queue[0]; }; /** * Returns whether the queue is empty. * @return {boolean} */ MyQueue.prototype.empty = function() { return this._queue.length === 0; }; /** * Your MyQueue object will be instantiated and called as such: * var obj = new MyQueue() * obj.push(x) * var param_2 = obj.pop() * var param_3 = obj.peek() * var param_4 = obj.empty() */