Given a binary tree, flatten it to a linked list in-place. For example,Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 思路: 用先序遍历,得到的是从小到大的顺序.把先序遍历变形一下: void flatten(TreeNode* root) { if(NULL == root) return; vec…

随笔一记,留做重温! Flatten Binary Tree to Linked List Given a binary tree, flatten it to a linked list in-place. For example, Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 第一个想法是先序遍历,然后按照访问顺序,添加右结点. public static void…

题目: Given a binary tree, flatten it to a linked list in-place. For example,Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 思路: 按照树的先序遍历顺序把节点串联起来即可. /** * Definition for a binary tree node. * function TreeNode(va…

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 日期 题目地址:https://leetcode.com/problems/binary-tree-cameras/ 题目描述 Given a binary tree, we install cameras on the nodes of the tree. Each camera at a node can monitor its parent,…

将左子树接到右子树之前,递归解决 void flatten(TreeNode *root) { if (root == nullptr)return; flatten(root->left); flatten(root->right); //如果没有左子树,直接返回即可 if (root->left == nullptr)return; p = root->left; //寻找左子树的最后一个结点 while (p->right)p = p->right; //将右结点…

题目 给定一个二叉树,原地将它展开为链表. 例如,给定二叉树 1 / \ 2 5 / \ \ 3 4 6 将其展开为: 1 \ 2 \ 3 \ 4 \ 5 \ 6 解析 通过递归实现:可以用先序遍历,然后串成链表 主要思想就是:先递归对右子树进行链表化并记录,然后将root->right指向 左子树进行链表化后的头结点,然后一直向右遍历子树,连接上之前的右子树 /** * Definition for a binary tree node. * struct TreeNode { * int v…

Given a binary tree, flatten it to a linked list in-place. For example,Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 解题思路: 看上去很简单,使用二叉树的中序遍历就可以实现.但是题目的小曲点在于要在原tree上修改,如果将左儿子放在右儿子位置上,会丢失右子树,导致遍历失败. 解决方法有两种: 1.不…

Given a binary tree, flatten it to a linked list in-place. For example, Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 思路:这题主要是就是前序遍历.主要解法就是将左子树转换为右支树,同一时候加入在右子树前.左子树求解时,须要主要左子树的深度. 详细代码例如以下: /** * Definition f…

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 Java解法 Python解法 日期 题目地址:https://leetcode.com/problems/binary-tree-tilt/#/description 题目描述 Given a binary tree, return the tilt of the whole tree. The tilt of a tree node is def…

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 迭代 日期 题目地址:https://leetcode.com/problems/binary-tree-paths/#/description 题目描述 Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Ex…

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 后序遍历 日期 题目地址:https://leetcode.com/problems/binary-tree-pruning/description/ 题目描述 We are given the head node root of a binary tree, where additionally every node's value is eith…

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 日期 题目地址:https://leetcode.com/problems/quad-tree-intersection/description/ 题目描述 A quadtree is a tree data in which each internal node has exactly four children: topLeft, topRigh…

Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list. For example,Given 1->2->3->3->4->4->5, return 1->2->5.Given 1->1->1->2->3, return 2->3.…

Follow up for "Search in Rotated Sorted Array":What if duplicates are allowed? Would this affect the run-time complexity? How and why? Write a function to determine if a given target is in the array. 我的思路: 太混乱了 不提了.注意关键区分依据 排好序的一定是从小到大的 看大神的吧: b…

Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element. For example,Given [3,2,1,5,6,4] and k = 2, return 5. 思路: 堆.讲解:二叉堆 class Solution { public: //新插入i结点 其父节点为(i…

[LeetCode]199. Binary Tree Right Side View 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/binary-tree-right-side-view/description/ 题目描述: Given a binary tree, imagine yourself standing on the right side of it, return the values of the no…

[LeetCode]652. Find Duplicate Subtrees 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/find-duplicate-subtrees/description/ 题目描述: Given a binary tree, return all duplicate sub…

[LeetCode]113. Path Sum II 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/path-sum-ii/description/ 题目描述: Given a binary tree and a sum, find all root-to-leaf paths where each…

[LeetCode]147. Insertion Sort List 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.me/ 题目地址:https://leetcode.com/problems/insertion-sort-list/description/ 题目描述: Sort a linked list using insertion sort. A graphical…

[LeetCode]299. Bulls and Cows 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/bulls-and-cows/description/ 题目描述: You are playing the following Bulls and Cows game with your friend: You write down…

[LeetCode]743. Network Delay Time 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/network-delay-time/description/ 题目描述: There are N network nodes, labelled 1 to N. Given times…

[LeetCode]518. Coin Change 2 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/coin-change-2/description/ 题目描述: You are given coins of different denominations and a total amount of money. Write a…

[LeetCode]474. Ones and Zeroes 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/ones-and-zeroes/description/ 题目描述: n the computer world, use restricted resource you have to generate maximum benef…

[LeetCode]731. My Calendar II 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/my-calendar-ii/description/ 题目描述: Implement a MyCalendarTwo class to store your events. A new event can be added if…

[LeetCode]785. Is Graph Bipartite? 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/is-graph-bipartite/description/ 题目描述: Given an undirected graph, return true if and only if it is bipartite. Re…

[LeetCode]895. Maximum Frequency Stack 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/maximum-frequency-stack/description/ 题目描述: Implement FreqStack, a class which simulates the operation of a…

[LeetCode]764. Largest Plus Sign 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/largest-plus-sign/description/ 题目描述: In a 2D grid from (0, 0) to (N-1, N-1), every cell contains a 1, except thos…

[LeetCode]738. Monotone Increasing Digits 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/monotone-increasing-digits/description/ 题目描述: Given a non-negative integer N, find th…

[LeetCode]436. Find Right Interval 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/find-right-interval/description/ 题目描述: Given a set of intervals, for each of the interval i,…

[LeetCode]851. Loud and Rich 解题报告(Python) 标签(空格分隔): LeetCode 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/loud-and-rich/description/ 题目描述: In a group of N people (labelled 0, 1, 2, -, N-1), each person ha…