백준
[10845] 큐
Jcoder
2018. 7. 22. 16:20
#include <iostream>#include <queue>#include <string>using namespace std;int main(){queue<int> q;int i, testcase;string str;cin >> testcase;for (i = 0; i < testcase; i++){cin >> str;if (str == "push"){int num;cin >> num;q.push(num);}else if (str == "pop"){if (!q.empty()){cout << q.front() << endl;q.pop();}elsecout << "-1\n";}else if (str == "size")cout << q.size() << endl;else if (str == "empty"){if (q.empty())cout << "1\n";elsecout << "0\n";}else if (str == "front"){if (!q.empty())cout << q.front() << endl;elsecout << "-1\n";}else if (str == "back"){if (!q.empty())cout << q.back() << endl;elsecout << "-1\n";}}return 0;}