The classification function, the function library is ctype.hint isalpha (int CH) if CH is the letter ('A' - 'Z', 'A' - 'Z') returns to a non-0 value, otherwise returns 0INT IsalNum (INT CH) CH is the letter ('A' - 'Z', 'A' - 'Z') or numbers ('0' - '9') returns to a non-0 value, otherwise returns 0INT ISASCII (int CH) if ch is a character (ASCII) 0-127 in the code returns a non-0 value, otherwise returns 0INT ISDIGIT (INT CH) if the CH is a number ('0' - '9') returns a non-0 value, otherwise returns 0INT ISGRAPH (INT CH) if CH is Print characters (excluding spaces) (0x21-0x7e) Returns non-0 value,
Otherwise, returning 0INT ISSPACE (INT CH) If the CH is space (''), horizontal tab ('/ t'), carriage returns ('/ r'), paper wrap ('/ f'), vertical system Table ('/ V'), the wrap ('/ n') returns a non-0 value, otherwise it returns 0INT ISUPPER (INT CH) if the CH is uppercase letters ('A' - 'Z') returns non-0 value, otherwise Returns 0INT TOLOWER (INT CH) If CH is uppercase letters ('A' - 'Z') Returns the corresponding lowercase letters ('A' - 'Z') Int Toupper (int CH) If Ch is lowercase letters ('A' -'z ') Returns the corresponding uppercase letter (' A '-' Z ')
