Program to sort given element using Heap Sort in C

/*
   Heap Sort Algorithm
   Created By: Pirate
*/

#include<stdio.h>

#include<conio.h>

int a[500],size;

void heap_sort(int a[]);

void build_max_heap(int a[]);

void max_heapify(int a[],int i);

int main()

{

     int i,s;

     printf("** HEAP SORT **");

     printf("\nEnter the No. of elements.\n");

     scanf("%d",&size);

     printf("Enter the %d elements:\n",size);

     for(i=0;i<size;i++)

     scanf("%d",&a[i]);

     size--;

     s=size;

     heap_sort(a);

     printf("********************************");

     printf("\nAfter Sorting\n");

     for(i=0;i<=s;i++)

     printf("%d\t",a[i]);

     getch();

}

void build_max_heap(int a[])

{

     int i;

     for(i=(size)/2;i>=0;i--)

     {

                           max_heapify(a,i);

     }

}

void max_heapify(int a[],int i)

{

     int l,r,temp,largest,j;

     l=i*2+1;

     r=i*2+2;

     if((l<=size) && a[l]>a[i])

     largest=l;

     else

     largest=i;

     if((r<=size) && a[r]>a[largest])

     largest=r;

     if(largest!=i)

     {

                   temp=a[i];

                   a[i]=a[largest];

                   a[largest]=temp;

                   max_heapify(a,largest);

     }

}

void heap_sort(int a[])

{

     int i,t;

     build_max_heap(a);

     for(i=size;i>=0;i--)

     {

                       t = a[0];

                       a[0] = a[i];

                       a[i] = t;

                       size=size-1;   

                       max_heapify(a,0);

     }

}


Output