백준 #14235 크리스마스 선물 C++

https://www.acmicpc.net/problem/14235

우선순위 큐

#include <iostream>
#include <string>
#include <vector>
#include <math.h>
#include <algorithm>
#include <utility>
#include <stack>
#include <queue>
#include <math.h>
#include <set>
#include <map>
#include <list>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <limits.h>

using namespace std;
using int64 = long long;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);

    priority_queue<int> pq;
    int n;
    cin >> n;
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;
        if (a == 0) {
            if (pq.empty()) cout << -1 << "\n";
            else {
                cout << pq.top() << "\n";
                pq.pop();
            }
        }
        else {
            for (int j = 0; j < a; j++) {
                int val;
                cin >> val;
                pq.push(val);
            }
        }
    }
}