leetcode [#104] | GCidea's blog

JerryXia 发表于 2018-04-21 06:31:31 , 阅读 (7)

1. 题目
2. 解决方案
3. 注意事项

题目

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.

解决方案

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
public class Solution {
    public int maxDepth(TreeNode root) {
        int depth = 0;
        if(root == null){
            return depth;
        } else {
            int l = 0;
            int r = 0;
            if(root.left != null){
                l = maxDepth(root.left);
            }
            if(root.right != null){
                r = maxDepth(root.right);
            }
            depth = l > r ? l : r;
            return depth + 1;
        }
    }
}

注意事项

　　思路是递归，根据二叉树的结构，某个子节点是其子树的根节点，则不断反复进行递归直到找到叶子节点，返回为零，其余不断加1，累计总长度（左右子节点均相同处理）。

[ 技术文章推荐 ]