26 lines
500 B
JavaScript
26 lines
500 B
JavaScript
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'use strict';
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var Queue = function () {
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this.head = null;
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this.tail = null;
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};
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Queue.prototype = {
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add: function (item) {
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var entry = { item: item, next: null };
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var tail = this.tail;
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if (tail) tail.next = entry;
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else this.head = entry;
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this.tail = entry;
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},
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get: function () {
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var entry = this.head;
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if (entry) {
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var next = this.head = entry.next;
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if (next === null) this.tail = null;
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return entry.item;
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}
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}
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};
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module.exports = Queue;
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