#include <ext/pb_ds/priority_queue.hpp>
template<typename T>
// greater<T> für Min-Queue
using priorityQueue = __gnu_pbds::priority_queue<T, less<T>>;

int main() {
	priorityQueue<int> pq;
	auto it = pq.push(5);   // O(1)
	pq.push(7);
	pq.pop();               // O(log n) amortisiert
	pq.modify(it, 6);       // O(log n) amortisiert
	pq.erase(it);           // O(log n) amortisiert
	priorityQueue<int> pq2;
	pq.join(pq2);           // O(1)
}