A.具有n個(gè)點(diǎn)的樹(shù)共有n-1個(gè)樹(shù)枝 B.樹(shù)中任意兩點(diǎn)間存在多條路徑 C.樹(shù)是連通的,去掉任一條邊便不連通 D.除單點(diǎn)樹(shù)外,樹(shù)至少有兩個(gè)端點(diǎn)度數(shù)為1