ACM Heap-Max/Heap sort (Stack)

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

vector<int> heap;

void insert(int x){
    heap.push_back(x);
    int v=heap.size()-1;
    while (v>1){
        if (heap[v]>heap[v/2]) swap(heap[v], heap[v/2]);
        else break;
        v/=2;
    }
}

int getMax(){
    int res=heap[1];
    heap[1]=heap.back();
    heap.pop_back();
    int v=1;
    while (v<heap.size()){
        int l=v*2, r=v*2+1;
        if (l<heap.size()){
            if (r<heap.size() && heap[r]>heap[l]){
                l=r;
            }
            if (heap[v]<heap[l]) {
                swap(heap[v], heap[l]);
            }
            v=l;
        } else break;
    }
    return res;
}

int main() {
    heap.push_back(0);
    int i, n=5;
    for (i=0; i<n; i++){
        int x;
        cin>>x;
        insert(x);
    }
    vector<int> stack;
    for (i=0; i<n; i++){
        stack.push_back(getMax());
    }
    for (i=0; i<n; i++){
        cout<<stack.back()<<" ";
        stack.pop_back();
    }

    return 0;
}