1 #include 
     
       2 #include 
      
        3 /* 4 1.以字符串作为参数 5 2.找出ASCII在1~127范围内的字符 6 3.去掉重复字符  7 */ 8  9 int GetString(char *str);10 11 int main(int argc, char *argv[])12 {13     char ch[] = "abcd123123123123123123";14     int num = 0;15     16     num = GetString(ch);17     18     printf("num = %d\n", num);19     return 0;20 } 21 22 int GetString(char *str)23 {24     /*第一步：先计算符合范围的ASCII*/25     unsigned int index;26     unsigned int n = 0;27     unsigned int i = 0, j, k = 0;  28     char flag; 29     char arr[strlen(str)];30     char newchar[strlen(str)];31     32     for(index = 0; index < strlen(str); index++)33     {34         if((str[index] >= 0) && (str[index] <= 127))35         {36             arr[n] = str[index];37             n++;38         }        39     } 40     41     while(arr[i] != '\0')  42     {  43         flag = 1;  44         for(j = 0; j < i; j++)  45         {  46             if(arr[i] == newchar[j])  47             {48                 flag = 0;  49             }     50         }  51         if(flag)  52         {53             newchar[k] = arr[i];54             k++;55         }56               57           i++;  58     }    59      60     newchar[k]='\0';  61     puts(newchar);  62     63     return k;64 }