algorithm - 二叉树的第一个共同祖先

Question

如果我有一个这样的二叉搜索树，那么节点 6 和 1 的最低共同祖先是什么？

Answer 1

根据 Lowest common ancestor 的维基百科定义我纠正自己:

The lowest common ancestor (LCA) is a concept in graph theory and computer science. Let T be a rooted tree with n nodes. The lowest common ancestor is defined between two nodes v and w as the lowest node in T that has both v and w as descendants (where we allow a node to be a descendant of itself).

所以是的，根据这个定义，正确答案是 6。如果这是一个面试问题，最好提前与面试官澄清。