【leetcode】235-Lowest Common Ancestor of a Binary Search Tree

problem

235. Lowest Common Ancestor of a Binary Search Tree

 二叉搜索树的性质

Lets review properties of a BST:
１．Left subtree of a node N contains nodes whose values are lesser than or equal to node N's value.
２．Right subtree of a node N contains nodes whose values are greater than node N's value.
３．Both left and right subtrees are also BSTs.

百科解释

二叉查找树（Binary Search Tree），（又：二叉搜索树，二叉排序树）它或者是一棵空树，或者是具有下列性质的二叉树： 
若它的左子树不空，则左子树上所有结点的值均小于它的根结点的值； 
若它的右子树不空，则右子树上所有结点的值均大于它的根结点的值； 
它的左、右子树也分别为二叉排序树。

参考

1. leetcode_235_Lowest Common Ancestor of a Binary Search Tree;

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