for (int i = 0; i < len; i++) { CharType typ = toCharType(s[i]); if (transfer[st].find(typ) == transfer[st].end()) { returnfalse; } else { st = transfer[st][typ]; } } return st == STATE_INTEGER || st == STATE_POINT || st == STATE_FRACTION || st == STATE_EXP_NUMBER || st == STATE_END; } };