68 lines
949 B
JavaScript
68 lines
949 B
JavaScript
class Node {
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/// value;
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/// next;
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constructor(value) {
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this.value = value;
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// TODO: Remove this when targeting Node.js 12.
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this.next = undefined;
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}
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}
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class Queue {
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// TODO: Use private class fields when targeting Node.js 12.
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// #_head;
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// #_tail;
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// #_size;
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constructor() {
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this.clear();
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}
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enqueue(value) {
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const node = new Node(value);
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if (this._head) {
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this._tail.next = node;
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this._tail = node;
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} else {
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this._head = node;
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this._tail = node;
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}
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this._size++;
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}
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dequeue() {
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const current = this._head;
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if (!current) {
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return;
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}
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this._head = this._head.next;
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this._size--;
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return current.value;
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}
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clear() {
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this._head = undefined;
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this._tail = undefined;
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this._size = 0;
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}
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get size() {
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return this._size;
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}
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* [Symbol.iterator]() {
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let current = this._head;
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while (current) {
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yield current.value;
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current = current.next;
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}
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}
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}
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module.exports = Queue;
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