shell_sort.c

   1 /*
   2
   3 Invented in 1959 by D. L. Shell
   4
   5 Sorts an array of integers
   6
   7 From Page 60 & 61.
   8
   9 */
  10
  11 #include <stdio.h>
  12
  13 void shellsort(int v[], int n)
  14 {
  15         int gap, i, j, temp;
  16
  17         for(gap = n/2; gap > 0; gap /=2)
  18         {
  19                 for(i = gap; i < n; i++)
  20                 {
  21                         for(j = i - gap; j >=0 && v[j]>v[j+gap]; j-=gap)
  22                         {
  23                                 temp = v[j];
  24                                 v[j] = v[j+gap];
  25                                 v[j+gap] = temp;
  26                         }
  27                 }
  28         }
  29 }
  30
  31 int main()
  32 {
  33         int data[10] = { 9, 12, 54, 90, 0, 100, 65, 32, 54, 81};
  34         int i;
  35
  36         for(i = 0; i < 10; ++i) { printf("%d\n", data[i]); }
  37
  38         shellsort(data, 10);
  39
  40         for(i = 0; i < 10; ++i) { printf("%d\n", data[i]); }
  41
  42         return 0;
  43 }