A.2n-1 B.2n+2 C.2n+1 D.2n
A.葉結(jié)點(diǎn) B.空結(jié)點(diǎn) C.樹根結(jié)點(diǎn) D.分支結(jié)點(diǎn)
A.16 B.30 C.12 D.18