Vanilla-priority-queue NPM

Vanilla Priority Queue

A javascript implementation of a priority queue backed by a binary heap.

Installation
Usage
API

Installation

npm i vanilla-priority-queue --save

Usage

const {  MinPriorityQueue, MaxPriorityQueue } = require('vanilla-priority-queue');

let minPriorityQueue = new MinPriorityQueue();
/*
    The insert operation takes an item and it's priority.
    The item argument can be anything.
    The priority argument must be provided as an integer value.
*/
minPriorityQueue.insert(3, 3);
minPriorityQueue.insert(10, 10);
minPriorityQueue.peek() // returns 3
minPriorityQueue.remove() // returns 3
minPriorityQueue.remove() // returns 10
minPriorityQueue.isEmpty() // returns true


let maxPriorityQueue = new MaxPriorityQueue();
maxPriorityQueue.insert(3, 3);
maxPriorityQueue.insert(10, 10);
maxPriorityQueue.peek() // returns 10
maxPriorityQueue.remove() // returns 10
maxPriorityQueue.remove() // returns 3
maxPriorityQueue.isEmpty() // returns true

API

Both the MaxPriorityQueue and MinPriorityQueue expose the following functions:

peek()

Returns the highest priority item in the queue in constant time. For a MaxPriorityQueue this is the max element. For a MinPriorityQueue this is the min element.

insert(item, priority)

The insert operation takes an item and it's priority and inserts the following object into the queue:

{
    item: item, 
    priority: priority
}

The item argument can be anything. The priority argument must be provided as an integer.

The operation completes in O(lg n) time.

remove()

Removes the highest priority item in the queue in O(lg n) time. For a MaxPriorityQueue this is the max element. For a MinPriorityQueue this is the min element.