题解 | 二叉搜索树的最近公共祖先

# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param root TreeNode类 
# @param p int整型 
# @param q int整型 
# @return int整型
#
class Solution:
    def lowestCommonAncestor(self , root: TreeNode, p: int, q: int) -> int:
        # write code here
        if not root:
            return 0
        while root:
            if p < root.val and q < root.val:
                root = root.left
            elif p > root.val and q > root.val:
                root = root.right
            else:
                return root.val
        return 0