65 lines
1.8 KiB
JavaScript
65 lines
1.8 KiB
JavaScript
// Copyright 2006 The Closure Library Authors. All Rights Reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS-IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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/**
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* @fileoverview Datastructure: Priority Queue.
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*
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*
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* This file provides the implementation of a Priority Queue. Smaller priorities
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* move to the front of the queue. If two values have the same priority,
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* it is arbitrary which value will come to the front of the queue first.
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*/
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// TODO(user): Should this rely on natural ordering via some Comparable
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// interface?
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goog.provide('goog.structs.PriorityQueue');
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goog.require('goog.structs.Heap');
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/**
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* Class for Priority Queue datastructure.
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*
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* @constructor
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* @extends {goog.structs.Heap}
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*/
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goog.structs.PriorityQueue = function() {
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goog.structs.Heap.call(this);
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};
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goog.inherits(goog.structs.PriorityQueue, goog.structs.Heap);
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/**
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* Puts the specified value in the queue.
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* @param {*} priority The priority of the value. A smaller value here means a
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* higher priority.
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* @param {*} value The value.
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*/
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goog.structs.PriorityQueue.prototype.enqueue = function(priority, value) {
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this.insert(priority, value);
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};
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/**
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* Retrieves and removes the head of this queue.
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* @return {*} The element at the head of this queue. Returns
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* undefined if the queue is empty.
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*/
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goog.structs.PriorityQueue.prototype.dequeue = function() {
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return this.remove();
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};
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