README.md
# node-structures
[](https://travis-ci.org/AlbertHambardzumyan/node-structures)
[](https://www.npmjs.com/package/node-structures)
[](https://codeclimate.com/github/AlbertHambardzumyan/node-structures)
[](https://raw.githubusercontent.com/AlbertHambardzumyan/node-structures/master/LICENSE)
[](https://github.com/AlbertHambardzumyan/node-structures/issues)
Basic Data Structures for use in JavaScript (server-side, client side)
# Description
The Library provides the following Data Structure Implementations
* [Stack](#stack)
* [Queue](#queue)
* [Priority Queue](#priority-queue)
* [Linked List](#linked-list)
# Installation
Server-side:
npm install node-structures
Client-side:
bower install node-structures
# Usage
###Stack
```` javascript
const Stack = require('node-structures').Stack;
let stack = new Stack();
/**
* Tests if this stack is empty.
* @returns {boolean} - true if and only if this stack contains no items; false otherwise.
*/
stack.isEmpty();
/**
* Pushes an item onto the top of this stack.
* @param item - the item to be pushed onto this stack.
* @return {boolean} - true if the item is pushed.
*/
stack.push(3);
/**
* Looks at the object at the top of this stack without removing it from the stack.
* @throws {Error} - if this stack is empty.
* @returns {*} - the object at the top of this stack (the last item of the Vector object).
*/
stack.peek();
/**
* Removes the object at the top of this stack and returns that object as the value of this function.
* @throws {Error} - if this stack is empty.
* @return {*} - the object at the top of this stack (the last item of the Vector object).
*/
stack.pop();
/**
* Returns the size of the stack.
* @returns {Number} - the size of the stack.
*/
stack.size();
````
###Queue
```` javascript
const Queue = require('node-structures').Queue;
let queue = new Queue();
/**
* Returns the size of the queue.
* @returns {Number} - the size of the queue.
*/
queue.size();
/**
* Tests if this queue is empty.
* @returns {boolean} - true if and only if this queue contains no items; false otherwise.
*/
queue.isEmpty();
/**
* Inserts the specified element into this queue.
* @param element - the element to add
* @return {boolean} Returns true
*/
queue.add(3);
/**
* Retrieves and removes the head of this queue. This method differs from poll only in that it throws an exception
* if this queue is empty.
* @throws {Error} when the queue is empty.
* @return {*} Returns the head of this queue
*/
queue.remove();
/**
* Retrieves and removes the head of this queue, or returns null if this queue is empty.
* @returns {*} Returns the head of this queue, or null if this queue is empty.
*/
queue.poll();
/**
* Retrieves, but does not remove, the head of this queue, or returns null if this queue is empty.
* @returns {*} Returns the head of this queue, or null if this queue is empty.
*/
queue.peek();
````
###Priority Queue
```` javascript
const PriorityQueue = require('node-structures').PriorityQueue;
/**
* Creates an empty PriorityQueue with default comparator.
*
* Default Comparator: Compares `a` and `b`, when `a > b` it returns a positive number, when `a` = `b` it returns 0,
* and when `a < b` it returns a negative number.
*/
let priorityQueue = new PriorityQueue();
/**
* Creates an empty PriorityQueue with custom comparator.
*
* (`a > b` - return a positive number, when `a` = `b` return 0, and when `a < b`) return a negative number.
*/
const comparator = function(a, b){
return a - b; // define your own one.
};
let priorityQueue = new PriorityQueue(comparator);
/**
* Returns the number of elements in this collection
*
* @returns {Number} - the number of elements in this collection
*/
priorityQueue.size();
/**
* Tests if this priority queue is empty.
*
* @returns {boolean} - true if and only if this priority queue contains no items; false otherwise.
*/
priorityQueue.isEmpty();
/**
* Inserts the specified element into this priority queue.
*
* @param element - the element to add
* @returns {boolean} Returns true
*/
priorityQueue.add(40);
/**
* Retrieves and removes the head of this priority queue, or returns null if this priority queue is empty.
*
* @returns {*} Returns the head of this priority queue, or null if this priority queue is empty.
*/
priorityQueue.poll();
/**
* Retrieves, but does not remove, the head of this priority queue, or returns null if this priority queue is empty.
*
* @returns {*} Returns the head of this priority queue, or null if this priority queue is empty.
*/
priorityQueue.peek();
````
###Linked List
```` javascript
const LinkedList = require('node-structures').LinkedList;
let linkedList = new LinkedList();
/**
* Tests if this LinkedList is empty.
* @returns {boolean} - true if and only if this LinkedList contains no items; false otherwise.
*/
linkedList.isEmpty();
/**
* Inserts the specified element at the beginning of this list.
* @param data - the element to add
*/
linkedList.addFirst("A");
/**
* Appends the specified element to the end of this list.
* @param data - the element to add
*/
linkedList.addLast("B");
/**
* Inserts the specified element at the specified position in this list.
* Shifts the element currently at that position (if any) and any subsequent elements to the right
* (adds one to their indices).
* @throws IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())
* @param index - index at which the specified element is to be inserted
* @param element - element to be inserted
*/
linkedList.add(1, "C");
/**
* Removes the element at the specified position in this list. Shifts any subsequent elements to the left
* (subtracts one from their indices).
* Returns the element that was removed from the list.
* @throws IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())
* @param index - the index of the element to be removed
* @returns {*} - the element previously at the specified position
*/
linkedList.remove(2);
/**
* Returns the element at the specified position in this list.
* @throws IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())
* @param index - index of the element to return
* @returns {*} - the element at the specified position in this list
*/
linkedList.get(1);
/**
* Returns the number of elements in this list.
* @returns {Number} - the number of elements in this list.
*/
linkedList.size();
/**
* Removes all of the elements from this list. The list will be empty after this call returns.
*/
linkedList.clear();
````
# License
MIT