heap sort in place geeks for geeks code example
Example: heap sort heapify and max heap in binary tree
Implementation of heap sort in C:
#include <stdio.h>
int main()
{
int heap[10], array_size, i, j, c, root, temporary;
printf("\n Enter size of array to be sorted :");
scanf("%d", &array_size);
printf("\n Enter the elements of array : ");
for (i = 0; i < array_size; i++)
scanf("%d", &heap[i]);
for (i = 1; i < array_size; i++)
{
c = i;
do
{
root = (c - 1) / 2;
if (heap[root] < heap[c]) /* to create MAX heap array */
{ // if child is greater than parent swap them
temporary = heap[root]; // as structure is of complete binary tree
heap[root] = heap[c]; // it took logn steps to reach from root to leaf
heap[c] = temporary;
}
c = root;
} while (c != 0);
}
printf("Heap array : ");
for (i = 0; i < array_size; i++)
printf("%d\t ", heap[i]); //printing the heap array
for (j = array_size - 1; j >= 0; j--)
{
temporary = heap[0];
heap[0] = heap[j] ; /* swap max element with rightmost leaf element */
heap[j] = temporary;
root = 0;
do
{
c = 2 * root + 1; /* left node of root element */
if ((heap[c] < heap[c + 1]) && c < j-1)
c++;
if (heap[root]<heap[c] && c<j) /* again rearrange to max heap array */
{
temporary = heap[root];
heap[root] = heap[c];
heap[c] = temporary;
}
root = c;
} while (c < j);
}
printf("\n The sorted array is : ");
for (i = 0; i < array_size; i++)
printf("\t %d", heap[i]);
}