(n+)/
(x的後繼是經x的雙親y的右子樹中最左下的葉結點)
()前驅 ()後繼
() ()y^lchild () ()x () () y ()x(編者注本題按中序線索化)
帶權路徑長度最小的二叉樹又稱最優二叉樹
() ()
() ()(不唯一)
n
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