You are given an undirected tree consisting of \(n\) vertices. An undirected tree is a connected undirected graph with \(n−1\) edges. Your task is to add the minimum number of edges in such a way that the length of the shortest path from the vertex 1…
An undirected, connected tree with N nodes labelled 0...N-1 and N-1 edges are given. The ith edge connects nodes edges[i][0]and edges[i][1] together. Return a list ans, where ans[i] is the sum of the distances between node i and all other nodes. Exam…
An undirected, connected tree with N nodes labelled 0...N-1 and N-1 edges are given. The ith edge connects nodes edges[i][0] and edges[i][1] together. Return a list ans, where ans[i] is the sum of the distances between node i and all other nodes. Exa…
LeetCode刷题记录 传送门 Description An undirected, connected treewith N nodes labelled 0...N-1 and N-1 edges are given. The ith edge connects nodes edges[i][0] and edges[i][1] together. Return a list ans, where ans[i] is the sum of the distances between nod…
Sum of Distances in Tree An undirected, connected tree with N nodes labelled 0...N-1 and N-1 edges are given. The ith edge connects nodes edges[i][0] and edges[i][1] together. Return a list ans, where ans[i] is the sum of the distances between node i…
There is an undirected connected tree with n nodes labeled from 0 to n - 1 and n - 1 edges. You are given the integer n and the array edges where edges[i] = [ai, bi] indicates that there is an edge between nodes ai and bi in the tree. Return an array…
这篇随笔是对Wikipedia上k-d tree词条的摘录, 我认为解释得相当生动详细, 是一篇不可多得的好文. Overview A \(k\)-d tree (short for \(k\)-dimensional tree) is a binary space-partitioning tree for organizing points in a \(k\)-dimensional space. \(k\)-d trees are a useful data structure for…
The problem: Given node P and node Q in a binary tree T. Find out the lowest common ancestor of the two nodes. Analysis: The answer of this problem could only be the following two cases: case 1: P or Q itself is the lowest common ancestor. P ........…
We are given a binary tree (with root node root), a targetnode, and an integer value K. Return a list of the values of all nodes that have a distance Kfrom the target node. The answer can be returned in any order. Example 1: Input: root = [3,5,1,6,2…
Time Limit: 10 Sec Memory Limit: 128 MBSubmit: 1235 Solved: 418[Submit][Status][Discuss] Description The course of Software Design and Development Practice is objectionable. ZLC is facing a serious problem .There are many points in K-dimensional sp…
在正文开始之前需要介绍一个人:Sean Sexton. 来自明尼苏达双城的软件工程师.最为出色的是他维护了两个博客:2,000Things You Should Know About C# 和 2,000 Things You Should Know About WPF .他以类似微博式的150字简短语言来每天更新一条WPF和C#重要又容易被遗忘的知识.Follow他的博客也有一段日子了,很希望能够分享给大家. 本系列我不仅会翻译他的每一个tip,也会加入自己开发之中的看法和见解.本系列我希望自…
题目链接:Balanced Binary Tree | LeetCode OJ Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as a binary tree in which the depth of the two subtrees of every node never differ by more tha…
题目链接:Same Tree | LeetCode OJ Given two binary trees, write a function to check if they are equal or not. Two binary trees are considered equal if they are structurally identical and the nodes have the same value. Tags: Depth-first Search 分析 很基本的一道深度优…
题目链接:Recover Binary Search Tree | LeetCode OJ Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing its structure. Note: A solution using O(n) space is pretty straight forward. Could you devise a constan…
题目链接:Validate Binary Search Tree | LeetCode OJ Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than the node's key. The right…
题目链接:Symmetric Tree | LeetCode OJ Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree is symmetric: 1 / \ 2 2 / \ / \ 3 4 4 3 But the following is not: 1 / \ 2 2 \ \ 3 3 Note: B…
