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

class MaxHeap {
public:
    int top() const;
    bool empty() const;

    void pop();
    void push(int value);

private:
    vector <int> heap;

    void siftUp(int index);
    void siftDown(int index);
};

int MaxHeap::top() const {
    return heap[0];
}

bool MaxHeap::empty() const {
    return heap.size() == 0;
}

void MaxHeap::push(int value) {
    heap.push_back(value);
    siftUp(heap.size() - 1);
}

void MaxHeap::pop() {
    heap[0] = heap.back();
    heap.pop_back();
    siftDown(0);
}

void MaxHeap::siftUp(int index) {
    while (index > 0) {
        int parent = (index - 1) / 2;

        if (heap[index] > heap[parent]) {
            swap(heap[index], heap[parent]);
            index = parent;
        } else {
            break;
        }
    }
}

void MaxHeap::siftDown(int index) {
    while (index * 2 + 1 < heap.size()) {
        int child1 = index * 2 + 1;
        int child2 = index * 2 + 2;

        int largest = index;
        if (child1 < heap.size() && heap[child1] > heap[largest]) {
            largest = child1;
        }
        if (child2 < heap.size() && heap[child2] > heap[largest]) {
            largest = child2;
        }

        if (largest != index) {
            swap(heap[index], heap[largest]);
            index = largest;
        } else {
            break;
        }
    }
}

int main() {
    MaxHeap q;

    q.push(5);
    q.push(10);
    q.pop();

    printf("%d\n", q.top());

    return 0;
}