模板实现排序

 1 // CmpTest.cpp : Defines the entry point for the console application.
 2 //
 3 
 4 #include "stdafx.h"
 5 
 6 #include <string.h>
 7 template <class T, class CMP_FUN>
 8 bool MySort(T* psArray, int i4Num, CMP_FUN CmpFun);
 9 
10 typedef struct __MYTEST__
11 {
12     int a;
13     int b;
14 } S_MYTEST;
15 
16 //a>b 从小到大
17 bool Cmp2(S_MYTEST &a, S_MYTEST &b)
18 {
19     return (a.a > b.a);
20 }
21 
22 //a>b 从大到小
23 bool Cmp3(int &a, int &b)
24 {
25     return (a < b);
26 }
27 
28 
29 int main(int argc, char* argv[])
30 {
31     int array[10] = {1,2,3,4,6,7,5};
32     MySort(array, 10, Cmp3);
33     
34     S_MYTEST stMyTest[5] = {{1,2},{0,3},{10,9},{11,8},{23,1}};
35     MySort(stMyTest, 5, Cmp2);
36     
37     return 0;
38 }
39 
40 
41 //选择排序
42 template <class T, class CMP_FUN>
43 bool MySort(T* psArray, int i4Num, CMP_FUN CmpFun)
44 {
45     int i4Count = 1;//次数
46     int i4Index = 0; //索引
47 
48     T *psSelElement = 0; //记录的元素(最大或者最小)
49     T TempElement; //临时变量,用于数据交换
50     memset(&TempElement, 0, sizeof(T));
51     
52     //查找符合条件的元素 保存在 psSelElement
53     for (i4Count = 1; i4Count < i4Num; i4Count++)
54     {
55         psSelElement = &psArray[0]; //初始为第一个元素
56         for (i4Index = 1; i4Index <= i4Num - i4Count; i4Index++)
57         {
58             if (NULL == psSelElement)
59             {
60                 return false;
61             }
62             if (CmpFun(psArray[i4Index], *psSelElement))
63             {
64                 psSelElement = &psArray[i4Index];//修改为满足要求的元素
65             }
66         }
67 
68         //将psSelElement 替换到 最后的位置(i4Num - i4Count)
69         if (psSelElement != &psArray[i4Num - i4Count])
70         {
71             memcpy(&TempElement, &psArray[i4Num - i4Count], sizeof(T));
72             memcpy(&psArray[i4Num - i4Count], psSelElement, sizeof(T));
73             if (NULL == psSelElement)
74             {
75                 return false;
76             }
77             memcpy(psSelElement, &TempElement, sizeof(T));
78         }
79     }
80 
81     return true;
82 }