Reference: http://blog.csdn.net/v_july_v/article/details/18312089 http://leetcode.com/2011/07/lowest-common-ancestor-of-a-binary-tree-part-ii.html (1) Is the tree a BST or not? BST的话,我们就能按照BST的定义思考了.当前遍历的node如果比我们要找的两个点都大,说明那两个点都在当前node的左边,所以这两个node…