回複：details? please!

來源: 於 2010-04-16 16:00:53 [舊帖] [給我悄悄話] 本文已被閱讀：次

I use graph doing this question.6 is spacial,it should be between in the 1and 5.We get 5! If 6 out get new and cancel
cases are the same.Put 2,4 together 1,5,3 and 24 ,we have 2*4!cases should be canceled....Thank you.