Array Heap Sort

				
//**************************************
// Name: Array Heap Sort
// Description:Sorting an array using heap sort
// By: Debjit Kar
//
//This code is copyrighted and has// limited warranties.Please see http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=9538&lngWId=3//for details.//**************************************

#include <stdio.h>
//prototype
void fnSortHeap(int[], int);
//main
void main()
{
	int i, arr_num_items;
	int arr[] = {7,10,25,17,23,27,16,19,37,42,4,33,1,5,11};
	//total number of items in array.
	//if you do not provide the exact number you might get unwanted results
	arr_num_items = 15;
	//call fnSortHeap function for (arr_num_items - 2) times.
	for(i=arr_num_items; i>1; i--)
	{
		fnSortHeap(arr, i - 1);
	}
	//print the sorted array
	printf("\nThe Sorted Array\n----------------\n");
	for (i = 0; i < arr_num_items; i++)
		printf("%d\n",arr[i]);
	return;
}
//sort heap
void fnSortHeap(int arr[], int arr_ubound)
{
int i,o;
int lChild, rChild, mChild, root, temp;
//find the root element of the current element
root = (arr_ubound-1)/2;
//creating the heap
for(o=root;o>=0;o--)
{
 for(i=root;i>=0;i--)
 {
lChild = (2*i)+1;
rChild = (2*i)+2;
	if ((lChild <= arr_ubound) && (rChild <= arr_ubound))
{
 if(arr[rChild] >= arr[lChild])
mChild = rChild;
 else
mChild = lChild;
}
else
{
 if(rChild > arr_ubound)
mChild = lChild;
 else
mChild = rChild;
}
//swap elements
if (arr[i] < arr[mChild])
{
 temp = arr[i];
 arr[i] = arr[mChild];
 arr[mChild] = temp;
}
 }
}
//move the max element to the end of the array
temp = arr[0];
arr[0] = arr[arr_ubound];
arr[arr_ubound] = temp;
return;
}