#include <bits/stdc++.h>
using namespace std;

void siftDown(int* arr, int len, int index) {
    while (index * 2 + 1 < len) {
        int child1 = index * 2 + 1;
        int child2 = index * 2 + 2;

        int largest = index;
        if (child1 < len && arr[child1] > arr[largest]) {
            largest = child1;
        }
        if (child2 < len && arr[child2] > arr[largest]) {
            largest = child2;
        }

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

void heapSort(int* arr, int n) {
    for (int i = n / 2 - 1; i >= 0; i--) {
        siftDown(arr, n, i);
    }

    for (int i = n - 1; i >= 0; i--) {
        swap(arr[0], arr[i]);
        siftDown(arr, i, 0);
    }
}

void printArray(int* arr, int n) {
    if (n > 0) printf("%d", arr[0]);
    for (int i = 1; i < n; i++) {
        printf(" %d", arr[i]);
    }
    printf("\n");
}

int main() {
    int n = 5;
    int arr[] = {5, 1, 3, 2, 7};

    heapSort(arr, n);
    printArray(arr, n);

    return 0;
}