刷题-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.

递归

java解法：

public class Solution {

    public int maxDepth(TreeNode root) {
        if (root==null) return 0;
        int left = maxDepth(root.left);
        int right = maxDepth(root.right);
        return Math.max(left,right)+1;
    }

}

python解法：

# Definition for a  binary tree node
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Solution:
    # @param root, a tree node
    # @return an integer
    def maxDepth(self, root):
        if root is None:
            return 0
        else:
            return max(self.maxDepth(root.left),self.maxDepth(root.right))+1