题目

题目链接

https://leetcode.cn/problems/maximum-depth-of-binary-tree/?envType=study-plan-v2&envId=top-100-liked

解题思路

1. 深度优先遍历算法
2. 宽度优先遍历算法

相关代码

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

class Solution {
    public int maxDepth(TreeNode root) {
        Queue<TreeNode> queue = new LinkedList<>();
        if(root==null) return 0;
        int depth=0;
        queue.add(root);
        while(queue.size()!=0){
            int length = queue.size();
            depth++;
            for(int i=0;i<length;i++){
                TreeNode node = queue.poll();
                if(node.left!=null) queue.add(node.left);
                if(node.right!=null) queue.add(node.right);
            }
        }  
        return depth;  
    }
}