希尔排序

 1 // Shell sort, can be treated as a evolution of insert sort.
 2 void
 3 ShellSort(int arr[], int len)
 4 {
 5     // a common way of choosing increment: len, len/2, ..., 1
 6     for (int increment = len/2; increment > 0; increment /= 2) {
 7         // insert sort of array consist of elements separated by increment
 8         for (int i = increment; i < len; i++) {
 9             int tmp = arr[i];
10             int j;
11             for (j = i; j >= increment && arr[j-increment] > tmp; j -= increment) {
12                 arr[j] = arr[j-increment];
13             }
14             arr[j] = tmp;
15         }
16     }
17 }
18 
19 // Insert sort
20 void
21 InsertSort(int arr[], int len)
22 {
23     for (int i = 1; i < len; i++) {
24         int tmp = arr[i];
25         int j;
26         for (j = i; j >= 1 && arr[j-1] > tmp; j--) {
27             arr[j] = arr[j-1];
28         }
29         arr[j] = tmp;
30     }
31 }