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
        node = self.find_node(root, o1, o2)
        return node.val
    
    def find_node(self,root,o1,o2):
        if not root:
            return root
        if root.val==o1 or root.val==o2:
            return root
        left = self.find_node(root.left,o1,o2)
        right = self.find_node(root.right, o1, o2)
        if left and right:
            return root
        if left:
            return left
        if right:
            return right
        return None