题解 | #在二叉树中找到两个节点的最近公共祖先#

# 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 o1 int整型 
# @param o2 int整型 
# @return int整型
#
class Solution:
    def lowestCommonAncestor(self , root: TreeNode, o1: int, o2: int) -> int:
        # write code here
        # if find o1 or o2 in subtree with root
        def recur(root, o1, o2):
            if not root: return False 
            if root.val == o1 or root.val == o2: return root.val
            left = recur(root.left, o1, o2)
            right = recur(root.right, o1, o2)
            
            if left is False:
                return right
            else:
                if right is False: 
                    return left
                else:
                    return root.val
        return recur(root, o1, o2)