From 08147d132c4611e190d03a47bc870294d3cc1292 Mon Sep 17 00:00:00 2001 From: ZongqinWang <1722249371@qq.com> Date: Mon, 16 May 2022 14:28:02 +0800 Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=200232.=E7=94=A8=E6=A0=88?= =?UTF-8?q?=E5=AE=9E=E7=8E=B0=E9=98=9F=E5=88=97.md=20Scala=E7=89=88?= =?UTF-8?q?=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0232.用栈实现队列.md | 39 +++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/problems/0232.用栈实现队列.md b/problems/0232.用栈实现队列.md index 1a56d9f3..d9ba8e26 100644 --- a/problems/0232.用栈实现队列.md +++ b/problems/0232.用栈实现队列.md @@ -495,6 +495,45 @@ void myQueueFree(MyQueue* obj) { obj->stackOutTop = 0; } ``` +Scala: +```scala +class MyQueue() { + import scala.collection.mutable + val stackIn = mutable.Stack[Int]() // 负责出栈 + val stackOut = mutable.Stack[Int]() // 负责入栈 + // 添加元素 + def push(x: Int) { + stackIn.push(x) + } + + // 复用代码，如果stackOut为空就把stackIn的所有元素都压入StackOut + def dumpStackIn(): Unit = { + if (!stackOut.isEmpty) return + while (!stackIn.isEmpty) { + stackOut.push(stackIn.pop()) + } + } + + // 弹出元素 + def pop(): Int = { + dumpStackIn() + stackOut.pop() + } + + // 获取队头 + def peek(): Int = { + dumpStackIn() + val res: Int = stackOut.pop() + stackOut.push(res) + res + } + + // 判断是否为空 + def empty(): Boolean = { + stackIn.isEmpty && stackOut.isEmpty + } +} +``` -----------------------