1 #include 
     
         2 using namespace std;   3    4 char lmf(char *pString)   5 {   6     if(!pString)   7     {   8         return 0;   9     }  10     //定义并初始化hash表  11     unsigned int hash[256] = {
   0};  12       13     char *pHashKey = pString;  14     //根据字符串，计数！！！  15     while(*pHashKey != '\0')  16     {  17         hash[*pHashKey]++;  18         pHashKey++;  19     }  20     //复原  21     pHashKey = pString;  22     //再次遍历字符串，取得第一个只出现一次的字符  23     while(*pHashKey != '\0')  24     {  25         if(hash[*pHashKey] == 1)  26         {  27             return *pHashKey;  28         }  29         pHashKey++;  30     }  31     return 0;  32 }  33   34 void main()  35 {  36     char *a = "abbaccdeeffggh";  37     char ch = lmf(a);  38     putchar(ch);  39 }