Sort elements using heap sort - C Program

C program to sort 'n' numbers using heap sort.

Solution:

In heap sort, heap removes the largest element from the end of partially sorted array. Reconstruct the heap after removing largest element & again remove the largest element from remaining elements and place it at the end of partially sorted array. This process is repeated until no element is left in the heap.

#include<stdio.h>
#define MAX 100
void build_heap(int H[],int n)
{
      int i,j,k,v,heap;
      for(i=n/2;i>=1;i--)
      {
            k=i;
            v=H[k];
            heap=0;
            while(heap==0 && (2*k)<=n)
            {
                  j=2*k;
                  if(j<n)
                  {
                        if(H[j]<H[j+1])
                              j++;
                  }
                  if(v>=H[j])
                        heap=1;
                  else
                  {
                        H[k]=H[j];
                        k=j;
                  }
            }
            H[k]=v;
      }
}
void HeapSort(int heap[],int n)
{
      int t,i;
      for(i=n;i>=1;i--)
      {
            build_heap(heap,i);
            t=heap[1];
            heap[1]=heap[i];
            heap[i]=t;
      }
}
int main()
{
      int arr[MAX],size,i;
      printf("\tHeap sort\n");
      printf("-----------------------------------\n");
      printf(" How many numbers you want to sort?: ");
      scanf("%d",&size);
      printf("\n Enter %d numbers: \n",size);
      for(i=1;i<=size;i++)
            scanf("%d",&arr[i]);
      HeapSort(arr,size);
      printf("\n Sorted elements after using heap sort: \n\n");
      for(i=1;i<=size;i++)
      {
            printf("\t%d",arr[i]);
      }
      return 0;
}


Output:

heap sort
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