[LeetCode&Python] Problem 104. Maximum Depth of Binary Tree
Given a binary tree, find its maximum depth.
The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
Note: A leaf is a node with no children.
Example:
Given binary tree [3,9,20,null,null,15,7]
,
3 / \ 9 20 / \ 15 7
return its depth = 3.
# Definition for a binary tree node. # class TreeNode: # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution: def maxDepth(self, root): """ :type root: TreeNode :rtype: int """ if root==None: return 0 elif root.left==None and root.right==None: return 1 else: max1=self.maxDepth(root.left) max2=self.maxDepth(root.right) return 1+max(max1,max2)