leetcode_104_Maximum Depth of Binary Tree

描述：

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.

思路：

用递归，很简单，树为空时返回0，左子树为空且右子树为空时返回1，否则就返回左子树或右子树的最大深度再加1

代码：

class TreeNode{
		int val;
		TreeNode left;
		TreeNode right;
		TreeNode(int x){val=x;}
	}
	public int maxDepth(TreeNode root) {
		
        if(root==null)
        	return 0;
        if(root.left==null&&root.right==null)
        	return 1;
        int num1=maxDepth(root.left),num2=maxDepth(root.right);
        int num=(num1>=num2?num1:num2)+1;
        return num;
    }

结果：

leetcode_104_Maximum Depth of Binary Tree

原文：http://blog.csdn.net/mnmlist/article/details/44591453