[c++]백준 10828: 스택

www.acmicpc.net/problem/10828

10828번: 스택

#include <iostream>
#include <stack>
#include <string>

using namespace std;

int main() {
    stack<int> st;
    int n;
    cin >> n;
    while (n--) {
        string cmd;
        cin >> cmd;
        if (cmd == "push") {
            int x;
            cin >> x;
            st.push(x);
        } else if (cmd == "pop") {
            if (st.empty()) cout << -1 << endl;
            else {
                cout << st.top() << endl;
                st.pop();
            }
        } else if (cmd == "size") {
            cout << st.size() << endl;
        } else if (cmd == "empty") {
            if (st.empty())cout << 1 << endl;
            else cout << 0 << endl;
        } else if (cmd == "top") {
            if (st.empty()) cout << -1 << endl;
            else cout << st.top() << endl;
        }
    }
}