힙을 구현하려고 했고, 구현했는데, 고장이네요. 엉엉ㅇㅇㅇ어어어어어어어ㅓㅇㅇㅇㅇㅇ

heap.cpp

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

template<class T, class Comp=greater<T> >
struct heap{
	vector<T> data;
	Comp cmp;
	heap(){data.push_back({});}
	void push(T t){
		data.push_back(t);
		int idx=data.size()-1;
		while(idx>1){
			int up=idx>>1;
			if(cmp(data[idx],data[up]))
				swap(data[idx],data[up]);
			else break;
			idx=up;
		}
	}
	T top(){if(data.size()==1)return T{};else return data[1];}
	void pop(){
		if(data.size()==1)return;
		else if(data.size()==2){data.pop_back();return;}
		swap(data[1],data.back());
		data.pop_back();
		int ch;
		for(int idx=1;idx<<2<=data.size();idx=ch)
		{
			ch=idx<<1;
			if(ch+1!=data.size()&&cmp(data[ch|1],data[ch]))ch|=1;
			if(!cmp(data[idx],data[ch]))swap(data[idx],data[ch]);
			else break;
		}
	}
	bool empty(){return data.size()==1;}
};

int main() {
	heap<int> hp;
	for(int i=1;i<17;i++)hp.push(i);
	for(int i=1;i<17;i++){cout<<hp.top()<<endl;hp.pop();}
}