node-priority-queue

Install

npm install node-priority-queue

Description

node-priority-queue lets you create a priority queue(backed by heap). You can specify the property of object to set priority on to create either max-queue or min-queue.

Operations

• Get priority queue
• Peek
• Pop

Example 1

const node_priority = require('node-priority-queue');

Create an empty queue

node_priority.createEmptyQueue();

Add elements

node_priority.addElement({a : 100}); node_priority.addElement({a : -10}); node_priority.addElement({a : 13});

Property of object to set priority on (1 = ascending, -1 = descending)

node_priority.setPropertyToPrioritize("a", -1);

Get the priority queue

var queue = node_priority.getQueue();

Peek

var item = node_priority.peek();

Pop

var item = node_priority.pop();

If you pop an item from queue, then you need to call node_priority.getQueue() to get updated queue

Example 2

        var array = [];
        array.push({'a' : 1});
        array.push({'a' : 4});
        array.push({'a' : 2});
        array.push({'a' : 3});        
        node_priority.setInputArray(array);
        node_priority.setPropertyToPrioritize('a', 1);
        var queue = node_priority.getQueue();
        console.log(queue);
        queue.push({a : 1000});
        queue.push({a : -19});
        queue.push({a : 121});
        queue = node_priority.getQueue(queue);
        console.log(queue);