lgrthms/lib/dataStructures/PriorityQueue.js

Algorithms and data structures for your JavaScript and TypeScript projects 🧑‍💻

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.PriorityQueue = void 0;
const MaxHeap_1 = require("./MaxHeap");
class PriorityQueue {
    constructor() {
        this.MIN_PRIORITY = 0;
        const compareFn = (a, b) => a.priority - b.priority;
        this.heap = new MaxHeap_1.MaxHeap(compareFn);
    }
    get size() {
        return this.heap.size;
    }
    // O(log(n)) time | O(1) space
    enqueue(value, priority = this.MIN_PRIORITY) {
        if (priority < this.MIN_PRIORITY) {
            throw new Error('Cannot enqueue value, priority must be greater than or equal to 0');
        }
        this.heap.insert({ data: value, priority });
        return this.heap.size;
    }
    // O(log(n)) time | O(1) space
    dequeue() {
        const item = this.heap.extract();
        if (item) {
            return item.data;
        }
    }
    // O(1) time | O(1) space
    peek() {
        const item = this.heap.peek();
        if (item) {
            return item.data;
        }
    }
}
exports.PriorityQueue = PriorityQueue;