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