1 #include <iostream> 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 != ' ') 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 != ' ') 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 }