int findMaxSubstring(char* str)
{
    int maxLength = 0;
    int maxStartIndex = 0;
    int curLength = 0;
    int curStartIndex = 0;
    bool isFind = 0;
    for(unsigned int i = 0;i= 'a' && str[i] 'z')
        {
           isFind = 0;
           if(curLength > maxLength)
           {
              maxLength = curLength;
              maxStartIndex = curStartIndex;
              curLength = 0;
           }
        }
    }
    char *p = NULL;
    p = &str[maxStartIndex];
    while(*p >= 'a' && *p