1 #include <iostream>
2 using namespace std;
3 #include <stdlib.h>
4
5 #define LEN 12
6
7 int QuickSort(int *arr,int start,int end);
8 int Sort(int *arr,int start,int end);
9 int swap(int &a,int &b);
10
11 int main()
12 {
13 srand(16);
14 int A[LEN] = {13,19,9,5,12,8,7,4,21,2,6,11};
15 QuickSort(A,0,11);
16 for(int i = 0;i < LEN;i++)
17 {
18 cout<<A[i]<<endl;
19 }
20 }
21
22 int QuickSort(int *arr,int start,int end)
23 {
24 if(start < end)
25 {
26 int i = Sort(arr,start,end); //以主元i的位置为界限分割成俩个数组
27 QuickSort(arr,start,i -1);
28 QuickSort(arr,i + 1,end);
29 }
30 return 0;
31 }
32
33 int Sort(int *arr,int start,int end)
34 {
35 int piv = rand() % (end + 1 - start) + start; //随机选取主元
36 swap(arr[piv],arr[end]);
37 //i-j的范围为比主元小的值，j-end的范围为比主元大的值
38 int i = start - 1;
39
40 for(int k = start; k < end ; k++)
41 {
42 if(arr[k] <= arr[end])
43 {
44 i = i+1;
45 swap(arr[i],arr[k]);
46 }
47 }
48 swap(arr[i+1],arr[end]);
49 return i+1;
50 }
51
52 int swap(int &a,int &b)
53 {
54 int tmp;
55 tmp = a;
56 a = b;
57 b = tmp;
58 return 0;
59 }
