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LeetCode_Maximum Depth of Binary Tree

一.题目

Maximum Depth of Binary Tree

  Total Accepted: 70693 Total Submissions: 156776My Submissions

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.

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二.解题技巧

    这道题和Minimum Depth of Binary Tree类似,仅仅只是这个是求最大深度的。解法也和Minimum Depth of Binary Tree一样,都是对二叉树进行递归。然后将子树的最大深度进行返回。终于得到这个树的最大深度。
    这种方法的时间复杂度为O(n),空间复杂都为O(logn)。


三.实现代码

#include <iostream>

/**
* Definition for a binary tree node.
* struct TreeNode {
*     int val;
*     TreeNode *left;
*     TreeNode *right;
*     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/


struct TreeNode
{
    int val;
    TreeNode *left;
    TreeNode *right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

class Solution
{
public:
    int maxDepth(TreeNode* root)
    {
        if (!root)
        {
            return 0;
        }

        int Result = 1;
        int Left = maxDepth(root->left);
        int Right = maxDepth(root->right);

        if (Left * Right)
        {
            Result += Left < Right? Right : Left;
        }
        else
        {
            Result += Right + Left;
        }

        return Result;
    }
};




四.体会

    这是一道类似的题,仅仅是改改代码就能够实现了。



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posted on 2017-05-29 08:56  gavanwanggw  阅读(113)  评论(0编辑  收藏  举报