Today's Challenge

https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/

Lowest Common Ancestor of a Binary Search Tree - LeetCode

요즘 트리 문제가 많이 나옴.
순회 하면서 가장 적절한 root를 찾아서 리턴하면 되는 문제

class Solution:
    def lowestCommonAncestor(self, root: 'TreeNode', p: 'TreeNode', q: 'TreeNode') -> 'TreeNode':
        if (root == p or root == q or not root):
            return root
        
        left = self.lowestCommonAncestor(root.left, p, q)
        right = self.lowestCommonAncestor(root.right, p, q)
        
        if left and right:
            return root
        elif left:
            return left
        elif right:
            return right