heapsort cpp

#include<iostream>

using namespace std;

void przesiewanie(int q, int p, int *a) {
    int i = q, j = 2*i, x = a[i-1];

    while (j < p) {
        if (j < p) {
            if (a[j-1] > a[j]) {
                j++;
            }

            if (x <= a[j-1]) {
                goto end;
            }

            a[i-1] = a[j-1];
            i = j;
            j = 2*i;
        }
    }
    end:
    a[i-1] = x;
}

void stogowe(int n, int *a) {
    int q = (n/2) + 1;
    int p = n;
    int x;

    while (q > 1) {
        --q;
        przesiewanie(q, p, a);
    }

    while (p > 1) {
        x = a[0];
        a[0] = a[p-1];
        a[p-1] = x;
        --p;
        przesiewanie(q, p, a);
    }
}

int main() {
    int n = 30;

    int tab[n] = {-2, 86, -3, 51, 67, -14, 15, 9, 28, 1, 2, 6, 33, 13, 7, -4, 5, 95, 18, 12, 4, 50, 99, 8, 41, 77, 60, 3, 31};

    stogowe(n, tab);

    cout<<"\nElementy posortowane:\n";
    for(int i=0; i<n; i++)
            cout<<tab[i]<<" ";

    return 0;
}