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Regarding the heap sort algorithm.

I get the concept of the heap sort algorithm and its like first you have a heap(ordered binary tree) then we have the Max heap which has the highest element value in the array at the top of the tree. The parent nodes will be basically > than the child nodes. But I don't get the heapify sample code here. Can someone explain? Thank you.

```
#include <stdio.h>
void swap(int *a, int *b) {
int tmp = *a;
*a = *b;
*b = tmp;
}

//can someone explain the heapify function of the coding?
void heapify(int arr[], int n, int i) {
int max = i;  
int leftChild = 2 * i + 1; coding
int rightChild = 2 * i + 2;
//If left child is greater than root
if (leftChild < n && arr[leftChild] > arr[max])
max = leftChild;
//If right child is greater than max
if (rightChild < n && arr[rightChild] > arr[max])
max = rightChild;
//If max is not root
if (max != i) {
swap(&arr[i], &arr[max]);
//heapify the affected sub-tree recursively
heapify(arr, n, max);
}
}

//Main function to perform heap sort
void heapSort(int arr[], int n) {
//Rearrange array (building heap)
for (int i = n / 2 - 1; i >= 0; i--)
heapify(arr, n, i);
//Extract elements from heap one by one
for (int i = n - 1; i >= 0; i--) {
swap(&arr[0], &arr[i]); //Current root moved to the end
heapify(arr, i, 0); //calling max heapify on the heap reduced
}
}

//print size of array n using utility function
//print size of array n using utility function
void display(int arr[], int n) {
for (int i = 0; i < n; ++i)
printf("%d ", arr[i]);
printf("\n");
}
//main function coding not included```