PROG-T1021: Machine

#include <iostream>
#include <queue>
using namespace std;

priority_queue<int> q;
int ql, x;
char cmd;

int main(){

    scanf("%d", &ql);
    for(int i = 0; i < ql; ++i){
        scanf(" %c", &cmd);
        switch(cmd){
        case 'P':
            scanf("%d", &x);
            q.push(x);
            break;
        case 'Q':
            if(q.empty()){
                cout << "-1\n";
            } else {
                cout << q.top() << "\n";
                q.pop();
            }
        }
    }

    return 0;
}