From 03630f4f075bab21652f524e8cead218de9fbb00 Mon Sep 17 00:00:00 2001
From: Ren Baoshuo <i@baoshuo.ren>
Date: Tue, 3 Aug 2021 21:22:28 +0800
Subject: [PATCH] =?UTF-8?q?828.=20=E6=A8=A1=E6=8B=9F=E6=A0=88?=
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https://www.acwing.com/problem/content/submission/code_detail/6873731/
---
 AcWing/828/828.cpp | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 AcWing/828/828.cpp

diff --git a/AcWing/828/828.cpp b/AcWing/828/828.cpp
new file mode 100644
index 00000000..b478b990
--- /dev/null
+++ b/AcWing/828/828.cpp
@@ -0,0 +1,22 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main() {
+    int m;
+    cin >> m;
+    stack<int> q;
+    while (m--) {
+        string op;
+        cin >> op;
+        if (op == "push") {
+            int x;
+            cin >> x;
+            q.push(x);
+        }
+        if (op == "pop") q.pop();
+        if (op == "empty") cout << (q.empty() ? "YES" : "NO") << endl;
+        if (op == "query") cout << q.top() << endl;
+    }
+    return 0;
+}