#include <stdio.h>

  void swap(int *a, int *b) {
    int tempvar = *a;
    *a = *b;
    *b = tempvar;
  }

  void heapify(int arr[], int n, int i) {
    int greatest = i;
    int leftSide = 2 * i + 1;
    int rightSide = 2 * i + 2;

    if (leftSide < n && arr[leftSide] > arr[greatest])
      greatest = leftSide;

    if (rightSide < n && arr[rightSide] > arr[greatest])
      greatest = rightSide;
    if (greatest != i) {
      swap(&arr[i], &arr[greatest]);
      heapify(arr, n, greatest);
    }
  }

  void heapSort(int arr[], int n) {
    for (int i = n / 2 - 1; i >= 0; i--)
      heapify(arr, n, i);


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

      heapify(arr, i, 0);
    }
  }

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


  int main() {
    int arr[] = {1, 12, 9, 5, 6, 10};
    int n = sizeof(arr) / sizeof(arr[0]);

    heapSort(arr, n);

    printf("Array ordenado com heapsort \n");
    printArray(arr, n);
  }