(3)--折半插入排序

 1 #include <iostream>
 2 using namespace std;
 3 void BInsertSort(int *arr,int length)
 4 {
 5     for (int i = 1; i <= length - 1;i++) {//从第一个元素开始插入
 6         int low = 0; int high = i-1; int key = arr[i];
 7         if (arr[i]<arr[i-1]) {//如果arr[i]<arr[i-1]，则寻找要插入的位置
 8             while (low <= high) {
 9                 int mid = (low + high) / 2;
10                 if (arr[mid]>key) {
11                     high = mid - 1;
12                 }
13                 else {
14                     low = low + 1;
15                 }
16             }
17         }
18         //移位
19         for (int j = i-1; j >=low;j--) {
20             arr[j+1] = arr[j];
21         }
22         arr[low] = key;//也可以为arr[high+1]=key
23     }
24 }
25 int main()
26 {
27     int arr[10] = {9,2,1,4,5,3,7,6,8,0};
28     BInsertSort(arr,10);
29     for (int i = 0; i < 10;i++) {
30         cout << arr[i] << " ";
31     }
32     return 0;
33 }