<OFFER05> 05_ReplaceSpaces

 void ReplaceBlank(char str[], int length) // length >= the real length of string
 {
     if (str == nullptr || length <= )
     {
         return;
     }
     int origin_str_len = ;
     int new_str_len = ;
     int i = ;
     int count_space = ;
     while (str[i] != '\0')
     {
         if (str[i] == ' ')
             ++count_space;
         ++origin_str_len;
         ++i;

     }
     new_str_len = origin_str_len +  * count_space;
     if (new_str_len > length)
         return;

     while (origin_str_len >=  && new_str_len > origin_str_len)
     {
         if (str[origin_str_len] == ' ')
         {
             str[new_str_len--] = '';
             str[new_str_len--] = '';
             str[new_str_len--] = '%';

         }
         else
         {
             str[new_str_len--] == str[origin_str_len];
         }
         --origin_str_len;
     }

 }