/* Program of sorting using shell sort */
#include <stdio.h>#define MAX 20
main()
{
int arr[MAX], i,j,k,n,incr;
printf("Enter the number of elements : ");
scanf("%d",&n);
for(i=0;i<n;i++)
{
printf("Enter element %d : ",i+1);
scanf("%d",&arr[i]);
}
printf("Unsorted list is :\n");
for (i = 0; i < n; i++)
printf("%d ", arr[i]);
printf("\nEnter maximum increment (odd value) : ");
scanf("%d",&incr);
/*Shell sort*/
while(incr>=1)
{
for(j=incr;j<n;j++)
{
k=arr[j];
for(i = j-incr; i >= 0 && k < arr[i]; i = i-incr)
arr[i+incr]=arr[i];
arr[i+incr]=k;
}
printf("Increment=%d \n",incr);
for (i = 0; i < n; i++)
printf("%d ", arr[i]);
printf("\n");
incr=incr-2; /*Decrease the increment*/
}/*End of while*/
printf("Sorted list is :\n");
for (i = 0; i < n; i++)
printf("%d ", arr[i]);
printf("\n");
}
