希尔排序例子

#include <stdio.h>
#include <time.h>

void shellsort(int a[], int l, int r)
{
    int h;
    //step 1 4 13 40 121 ...
    for(h=1; h<=(r-l)/9; h=h*3+1);
    for(; h>0; h=h/3)
    {
        for(int i=l+h; i<=r; i++)
        {
            int j=i;
            int v = a[i];
            while(j>=l+h && v<a[j-h])
            {
                a[j] = a[j-h];
                j -= h;
            }
            a[j] = v;
        }
    }
}

int main()
{
    int a[10] = {4,3,6,5,3,1,8,9,6,5};
    shellsort(a, 0, 9);
    for(int i=0; i<10; i++)
        printf("%d ", a[i]);
    printf("\n");
    return 0;
}