#include<iostream>

#include<vector>

#include<algorithm>

#include<utility>

#include<functional>

using namespace std;

class Heap

{

typedef function<bool(int, int)> compare;

private:

vector<int> _vec;

int heapsize;

compare comp;

public:

//default minheap

Heap(compare c = less<int>()): heapsize(0), comp(c) {}

~Heap() = default;

//c++11 construct with list

//such as Heap{4,3,2,1}

Heap(initializer_list<int> list, compare c = less<int>()): _vec(list.begin(), list.end()), heapsize(list.size()), comp(c)

{

for (int i = heapsize / 2 - 1; i >= 0; --i)

siftdown(i, comp);

}

//construct with vector

Heap(vector<int> vec, compare c = less<int>()): _vec(vec.begin(), vec.end()), heapsize(vec.size()), comp(c)

{

for (int i = heapsize / 2 - 1; i >= 0; --i)

siftdown(i, comp);

}

void siftdown(int pos, compare comp);

void insert(int value);

int remove(int pos);

int removeroot();

int size() const

{

return heapsize;

}

bool isLeaf(int pos) const

{

return pos >= heapsize / 2 && pos < heapsize;

}

int parent(int pos) const

{

return (pos - 1) / 2;

}

int leftchild(int pos) const

{

return pos * 2 + 1;

}

int rightchild(int pos) const

{

return pos * 2 + 2;

}

void printHeap()

{

for (int i = 0; i < heapsize; i++)

{

cout << _vec[i] << " ";

}

cout << endl;

}

};