From db17ec878d9159461d60c95c38fa38c1669af323 Mon Sep 17 00:00:00 2001
From: Ruvikm <1092045998@qq.com>
Date: Thu, 21 Jan 2021 15:40:46 +0800
Subject: [PATCH] Create P85.3.cpp

---
 栈和队列/队列/P85.3.cpp | 91 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 91 insertions(+)
 create mode 100644 栈和队列/队列/P85.3.cpp

diff --git a/栈和队列/队列/P85.3.cpp b/栈和队列/队列/P85.3.cpp
new file mode 100644
index 0000000..f59ec4f
--- /dev/null
+++ b/栈和队列/队列/P85.3.cpp
@@ -0,0 +1,91 @@
+#include <iostream>
+#include <vector>
+#include <stack>
+using namespace std;
+
+#define ElemType int
+#define MaxSize 3
+
+//P85.3
+//利用两个栈S1, S2来模拟一个队列, 已知栈的4个运算定义如下
+//	Push(s, x);				//元素x入栈S
+//	Pop(s, X);				//S出栈并将出栈的值赋给x
+//	StackEmpty(s);			//判断栈是否为空
+//	Stackoverflow(s);		//判断栈是否满
+
+//	如何利用栈的运算来实现该队列的3个运算(形参由读者根据要求自己设计) ?
+//	Enqueue					//将元素x入队
+//	Dequeue					//出队,并将出队元素存储在ⅹ中
+//	QueueEmpty				//判断队列是否为空
+
+bool Enqueue(stack<int> &S1, stack<int> &S2,ElemType x) {
+	if (S1.size() != MaxSize) {
+		S1.push(x);
+		return true;
+	}
+	if (S1.size() == MaxSize && !S2.empty()) {
+		cout << "队列已满！" << endl;
+		return false;
+	}
+	if (S1.size() == MaxSize && S2.empty()) {
+		while (!S1.empty()) {
+			int temp = S1.top();
+			S1.pop();
+			S2.push(temp);
+		}
+		S1.push(x);
+		return true;
+	}
+}
+
+bool Dequeue(stack<int> &S1, stack<int> &S2, ElemType &x) {
+	if (!S2.empty()) {
+		x = S2.top();
+		S2.pop();
+		return true;
+	}
+	if (S1.empty() && S2.empty()) {
+		cout << "队列为空！" << endl;
+		return false;
+	}
+	if (!S1.empty() && S2.empty()) {
+		while (!S1.empty()) {
+			int temp = S1.top();
+			S1.pop();
+			S2.push(temp);
+		}
+		x = S2.top();
+		S2.pop();
+		return true;
+	}
+}
+
+bool QueueEmpty(stack<int> S1, stack<int> S2) {
+	return (S1.empty() && S2.empty());
+}
+
+
+int main()
+{
+	//test
+	stack<int> S1, S2;
+
+	cout << QueueEmpty(S1, S2) << endl;
+
+	Enqueue(S1, S2, 1);
+	Enqueue(S1, S2, 2);
+	Enqueue(S1, S2, 3);
+	Enqueue(S1, S2, 4);
+
+	int x;
+	Dequeue(S1, S2, x);
+	cout << x << endl;
+	Dequeue(S1, S2, x);
+	cout << x << endl;
+	Dequeue(S1, S2, x);
+	cout << x << endl;
+	Dequeue(S1, S2, x);
+	cout << x << endl;
+	return 0;
+}
+