C(6,3)=20，他后面又乘了3，包含你说的情况

来源: 老石于 2012-12-28 21:29:20 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.