Merge pull request #2199 from syuilo/patch-2176

Resolve #2176

1 files changed, 33 insertions, 0 deletions

diff --git a/src/misc/queue.ts b/src/misc/queue.ts
new file mode 100644
index 0000000000..410878ba8b
--- /dev/null
+++ b/src/misc/queue.ts
@@ -0,0 +1,33 @@
+type Node<T> = { value: T, next: Node<T> };
+
+export default class Queue<T> {
+	private top: Node<T> = null;
+	private rear: Node<T> = null;
+	public length: number = 0;
+
+	public push(value: T): void {
+		const node: Node<T> = { value, next: null };
+		if (this.top === null) {
+			this.top = node;
+			this.rear = node;
+		} else {
+			this.rear.next = node;
+			this.rear = node;
+		}
+		this.length++;
+	}
+
+	public pop(): void {
+		this.top = this.top.next;
+		if (this.top == null) this.rear = null;
+		this.length--;
+	}
+
+	public toArray(): T[] {
+		const arr: T[] = Array<T>(this.length);
+		for (let node = this.top, i = 0; node !== null; node = node.next, i++) {
+			arr[i] = node.value;
+		}
+		return arr;
+	}
+}