答案(点此获取答案解析)
24\uff1bABC\u3001ACB\u3001ACD\u3001ADC\u3001ABD\u3001ADB\u3001BCD\u3001BDC\u3001BAC\u3001BCA\u3001BAD\u3001BDA\u3001CBA\u3001CAB\u3001CAD\u3001CDA\u3001CBD\u3001CDB\u3001DAB\u3001DBA\u3001DAC\u3001DCA\u3001DBC\u3001DCB\uff1b24\uff1bABCD\u3001ABDC\u3001A