单项选择题
A.n-1 B.n(n-1) C.n D.n+1
A.GEDHFBCA B.DGEBHFCA C.ABCDEFGH D.ACBFEDHG
A.12 B.13 C.14 D.15
A.32 B.31 C.16 D.15
微信扫一扫,加关注免费搜题