mathball/lib/priority-queue/index.js

A JavaScript library for Competitive Programming

'use strict';

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

var validateNumber = require('../validation/number');

var PriorityQueue = function () {
	function PriorityQueue() {
		_classCallCheck(this, PriorityQueue);

		this.queueArr = [];
	}

	// show the current queue


	_createClass(PriorityQueue, [{
		key: 'queue',
		value: function queue() {
			return this.queueArr.join(' ');
		}

		// enqueue method

	}, {
		key: 'push',
		value: function push(elem) {
			validateNumber(elem, 'PriorityQueue.push');

			var flag = false;

			for (var i in this.queueArr) {
				if (this.queueArr[i] > elem) {
					this.queueArr.splice(i, 0, elem);
					flag = true;
					break;
				}
			}

			if (!flag) {
				this.queueArr.push(elem);
			}

			return true;
		}

		// dequeue

	}, {
		key: 'pop',
		value: function pop() {
			if (this.queueArr.length === 0) {
				return 'Queue Underflow';
			}
			return this.queueArr.pop();
		}

		// front of the priority queue

	}, {
		key: 'front',
		value: function front() {
			if (this.queueArr.length === 0) {
				return 'Queue Underflow';
			}
			return this.queueArr[0];
		}

		// rear of the priority queue

	}, {
		key: 'rear',
		value: function rear() {
			if (this.queueArr.length === 0) {
				return 'Queue Underflow';
			}
			return this.queueArr[this.queueArr.length - 1];
		}

		// returns if the queue is empty or not

	}, {
		key: 'empty',
		value: function empty() {
			return this.queueArr.length === 0 ? true : false;
		}

		// should return the queue size

	}, {
		key: 'size',
		value: function size() {
			return this.queueArr.length;
		}
	}]);

	return PriorityQueue;
}();

module.exports = PriorityQueue;