思路: 使用单调栈可以达到O(n). 实现: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: TreeNode* constructMaximumBina…

654. Maximum Binary Tree 题目大意: 意思就是给你一组数,先选一个最大的作为根,这个数左边的数组作为左子树,右边的数组作为右子树,重复上一步. 读完就知道是递归了. 这个题真尼玛恶心,对JavaScript的友好度简直为0,用Js的可以直接放弃了. function TreeNode(val) { this.val = val this.left = this.right = null } var constructMaximumBinaryTree = function…

Maximum Binary Tree 题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/maximum-binary-tree/description/ Description Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in…

https://leetcode.com/problems/maximum-binary-tree-ii/ 在654. Maximum Binary Tree版本的建树基础上,在最后插入一个数. 新节点要么为根节点,原树为其左子树:要么将新节点插在右子树中. class Solution { public: TreeNode* insertIntoMaxTree(TreeNode* root, int val) { if(root == NULL) { root = new TreeNode(v…

Leetcode之分治法专题-654. 最大二叉树(Maximum Binary Tree) 给定一个不含重复元素的整数数组.一个以此数组构建的最大二叉树定义如下: 二叉树的根是数组中的最大元素. 左子树是通过数组中最大值左边部分构造出的最大二叉树. 右子树是通过数组中最大值右边部分构造出的最大二叉树. 通过给定的数组构建最大二叉树,并且输出这个树的根节点. 示例 : 输入:[3,2,1,6,0,5] 输出:返回下面这棵树的根节点: 6 / \ 3 5 \ / 2 0 \ 1 提示: 给定的数组…

题目如下: We are given the root node of a maximum tree: a tree where every node has a value greater than any other value in its subtree. Just as in the previous problem, the given tree was constructed from an list A (root = Construct(A)) recursively with…

Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum number…

Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum number…

We are given the root node of a maximum tree: a tree where every node has a value greater than any other value in its subtree. Just as in the previous problem, the given tree was constructed from an list A (root = Construct(A)) recursively with the f…

［抄题］: Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum…

Question Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maxim…

题目: Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum nu…

题目如下: Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 递归 日期 题目地址:https://leetcode.com/problems/maximum-binary-tree-ii/ 题目描述 We are given the root node of a maximum tree: a tree where every node has a value greater than any other v…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 递归 日期 题目地址:https://leetcode.com/problems/maximum-binary-tree/description/ 题目描述 Given an integer array with no duplicates. A maximum tree building on this array is defined as fol…

网址:https://leetcode.com/problems/maximum-binary-tree/ 参考: https://leetcode.com/problems/maximum-binary-tree/discuss/106146/C%2B%2B-O(N)-solution 我自己的做法是依照题意的逻辑,逐一递归的做法. O(n2) /** * Definition for a binary tree node. * struct TreeNode { * int val; * T…

Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum number…

Given an integer array with no duplicates. A maximum tree building on this array is defined as follow: The root is the maximum number in the array. The left subtree is the maximum tree constructed from left part subarray divided by the maximum number…

用一个整型数组构建一个二叉树,根结点是数组中的最大值,左右子树分别是根结点的值在数组中左右两边的部分. 分析,这是二叉树中比较容易想到的问题了,直接使用递归就行了,代码如下: class Solution(object): def constructMaximumBinaryTree(self, nums): """ :type nums: List[int] :rtype: TreeNode """ if not nums: return No…

1.题目描述 2.分析 找出最大元素,然后分割数组调用. 3.代码 TreeNode* constructMaximumBinaryTree(vector<int>& nums) { int size = nums.size(); ) return NULL; TreeNode *dummy = ); maxcont(dummy->left, , size-, nums); return dummy->left; } void maxcont(TreeNode* &…

https://leetcode.com/problems/maximum-binary-tree/ 给定数组A,假设A[i]为数组最大值,创建根节点将其值赋为A[i],然后递归地用A[0,i-1]创建左子树,用A[i+1,n]创建右子树. 使用vector的assign函数,该函数的特性: Any elements held in the container before the call are destroyed and replaced by newly constructed elem…

每次找到数组中的最大值,然后递归的构建左右树 public TreeNode constructMaximumBinaryTree(int[] nums) { if (nums.length==0) return null; return builder(nums,0,nums.length-1); } public TreeNode builder(int[] nums,int sta,int end) { /* 思路就是每次找到最大值,然后分为两个子数组递归构建左右树 */ if (sta>…

Given a binary tree, find the maximum path sum. The path may start and end at any node in the tree. For example:Given the below binary tree, 1 / \ 2 3 Return 6. 这道求二叉树的最大路径和是一道蛮有难度的题,难就难在起始位置和结束位置可以为任意位置,我当然是又不会了,于是上网看看大神们的解法,看了很多人的都没太看明白,最后发现了网友Yu's…

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. 求二叉树的最大深度问题用到深度优先搜索DFS,递归的完美应用,跟求二叉树的最小深度问题原理相同.代码如下: C++ 解法一: class Solution { public: in…

Problem: 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. 初看本题第一印象为递归写法.首先找出终止条件:node == NULL.若未进入递归终止状态,则分左子树和又子树进行递归,最终返回累加最大的值.其代码如下: /*…

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. Have you met this question in a real interview? Yes Example Given a binary tree as follow:…

Binary Tree Maximum Path Sum Given a binary tree, find the maximum path sum. The path may start and end at any node in the tree. For example: Given the below binary tree, 1 / \ 2 3 Return 6. 递归求解. maxPathSum(root)跟maxPathSum(root.left)和maxPathSum(roo…

题目 Given a binary tree, find the maximum path sum. For this problem, a path is defined as any sequence of nodes from some starting node to any node in the tree along the parent-child connections. The path does not need to go through the root. For exa…

Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 比较左子树和右子树的深度,取小的那个返回上来,并+1. 需要注意的是如果没有左子树或右子树.那么无条件取存在的那一边子树深…

题目: Given a binary tree, find the maximum path sum. The path may start and end at any node in the tree. For example: Given the below binary tree, 1 / \ 2 3 Return 6. 解题思路: 最长路径和要分几种情况考虑,对于这样一个节点 cur / \ left right 设left是左子树的最长路径和,right是右子树的最长路径和,要求当前…