code: protected int charGroup(char c) {
      int         result;
  
      result = 0;
  
      if ( (c >= 'a') && (c <= 'z') )
        result = 2;
      else if ( (c >= '0') && (c <= '9') )
        result = 1;
  
      return result;
    }
docs: returns the group of the character: 0=special char, 1=number, 2=letter.
  
  @param c		the character to check
  @return		the group