PriorityQueue

An implementation of priority queue in javascript.

Installation

npm install priorityqueue

Example

importPriorityQueuefrom"priorityqueue";classPoint{constructor(x,y){this.x=x;this.y=y;}}constnumericCompare=(a,b)=>(a>b ? 1 : a<b ? -1 : 0);constcomparator=(a,b)=>{constx=numericCompare(a.x,b.x);consty=numericCompare(a.y,b.y);returnx ? x : y;};constpq=newPriorityQueue({ comparator });pq.push(newPoint(4,6));pq.push(newPoint(2,3));pq.push(newPoint(5,1));pq.push(newPoint(1,2));console.log(pq.pop());// => {x: 5, y: 1}console.log(pq.top());// => {x: 4, y: 6}pq.push(newPoint(3,4));pq.push(newPoint(6,5));console.log(pq.length);// => 5console.log(pq.top());// => {x: 6, y: 5}

References

• instance methods
• static methods

Variation

BinaryHeap(default)

Binary heap is a simple and efficient in almost cases.

cons:

• slow with large amount of items(over 10k)
• slow in merge operation especially

PairingHeap

pros:

• super fast in merge operation(constant time)

SkewHeap

pros:

• super fast in merge operation(constant time)

Not to use:

• with sequence completely sorted

Import specific implementation

importPriorityQueuefrom"priorityqueue";importBinaryHeapfrom"priorityqueue/BinaryHeap";importPairingHeapfrom"priorityqueue/PairingHeap";importSkewHeapfrom"priorityqueue/SkewHeap";console.log(PriorityQueue===BinaryHeap);// => true

TypeScript users

If your tsconfig specifies moduleResolution: "node" (whether implicitly or explicitly), use priorityqueue/lib/BinaryHeap instead of priorityqueue/BinaryHeap .