The world's fastest Javascript priority queue? Maybe?
Itsy bitsy teeny weeny priority queue implemented as a blazing fast binary heap in fewer than 30 lines of code (sort of .. ok there's a couple of lines with two statements).
Supports arbitrary objects including strings or, by passing a maximum tree size, will select the best TypedArray
for guaranteed compact memory usage (...won't somebody think of the mobiles T_T)
ran under Node v6.9.1
package | num items (push/pop) | time (seconds) |
---|---|---|
nanoq (v0.0.3) | 10,000,000 | 1.855 🔥 |
tinyQueue (v1.2.2) | 10,000,000 | 2.714 |
FastPriorityQueue (0.2.4) | 10,000,000 | 12.008 |
nanoq has four methods; push()
, pop()
, peek()
and length()
, all fairly self-explanatory oui?
Install via npm:
$ npm install nanoq
var nanoq = require('nanoq');
// nanoq is a "minheap" by default
var q = new nanoq();
q.push(30);
q.push(20);
q.push(10);
console.log(q.length()) // returns 3. length() is a method not a property
console.log(q.pop(), q.pop(), q.pop()); // returns 10, 20, 30
// Works with strings:
q = new nanoq();
q.push("dog");
q.push("pig");
q.push("cat");
// peek() returns the topmost item without pop()ing
console.log(q.peek()) // returns "cat"
// force a TypedArray by passing in a maximum number of heap items
q = new nanoq(255);
// Note: .push() accepts integers only in this mode
// use your own comparator, here is a maxheap
// (pass 0 or null for the 1st param if you want to use regular JS arrays)
q = new nanoq(null, function(a,b) {
return a < b;
});
// add items to the maxheap
q.push(1);
q.push(2);
q.push(3);
console.log(q.pop(), q.pop(), q.pop()); // returns 3, 2, 1
// use your own custom objects
var stuff = [
{val: 3},
{val: 2},
{val: 1},
];
q = new nanoq(null, function(a, b){
return a.val > b.val
});
for (var s of stuff)
q.push(s);
console.log(q.pop(), q.pop(), q.pop()); // returns {val:1}, {val:2}, {val:3}