Shell Sort

shellsort.c

void shellsort(int *a, int n) 
{
    int h, i, j, k;
    for (h = n; h /= 2;) 
    {
        for (i = h; i < n; i++) 
        {
            k = a[i];
            for (j = i; j >= h && k < a[j - h]; j -= h) {
                a[j] = a[j - h];
            }
            a[j] = k;
        }
    }
}