Machine PROG 1021

#include<stdio.h>
#include<queue>

using namespace std;

int main()
{
    int k,i,x,ai;
    ai = 0;
    priority_queue<int> pq;
    scanf("%d",&k);
    int ans[k];
    i=0;
    char c;
    while(i<k){
        scanf(" %c",&c);
        if(c == 'P'){
            scanf("%d",&x);
            pq.push(x);
        }else if(c == 'Q'){
            if(pq.empty()){
                ans[ai] = -1;
            }
            else{
                ans[ai] = pq.top();
                pq.pop();
            }
            ai = ai + 1;
        }
        i = i + 1;
    }

    i = 0;
    while(i < ai){
        printf("%d\n",ans[i]);
        i = i + 1;
    }
    return 0;
}