https://oj.leetcode.com/problems/path-sum/ /** * Definition for binary tree * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ public class Solution { public boolean hasPathSum(TreeNode root,…
Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. Note: A leaf is a node with no children. Example: Given the below binary tree and sum = 22, 5 / \ 4 8…
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 给定一个二叉树和一个和,判断这个树中是否有一个从根到叶子的路径,使其这个路径上面的所有节点值的和为这个给定的值. 并且返回所有等于给定值的路径. 例如: 给定下面的二叉树,并且和为22. 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 返回true,因为这里面存在一个根到叶子的路径 5->4->11->…
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 给定一个二叉树和一个和,判断这个树中是否有一个从根到叶子的路径,使其这个路径上面的所有节点值的和为这个给定的值. 例如: 给定下面的二叉树,并且和为22. 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 返回true,因为这里面存在一个根到叶子的路径 5->4->11->2,使其他们的和为22. ++…
112. 路径总和 112. Path Sum 题目描述 给定一个二叉树和一个目标和,判断该树中是否存在根节点到叶子节点的路径,这条路径上所有节点值相加等于目标和. 说明: 叶子节点是指没有子节点的节点. 每日一算法2019/5/13Day 10LeetCode112. Path Sum 示例: 给定如下二叉树,以及目标和 sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 返回 true,因为存在目标和为 22 的根节点到叶子节点的路径 5->4->1…
这是小川的第381次更新,第410篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第243题(顺位题号是1022).给定二叉树,每个节点值为0或1.每个根到叶路径表示以最高有效位开始的二进制数.例如,如果路径为0 -> 1 -> 1 -> 0 -> 1,那么这可能表示二进制的01101,即13. 对于树中的所有叶子节点,请考虑从根到该叶子节点的路径所代表的数字.返回这些数字的总和. 例如: 1 / \ 0 1 / \ / \ 0 1 0 1 输入:[1,…
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 DFS 回溯 BFS 栈 日期 题目地址:https://leetcode.com/problems/path-sum/#/description 题目描述 Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up…
在Path SUm 1中(http://www.cnblogs.com/hitkb/p/4242822.html) 我们采用栈的形式保存路径,每当找到符合的叶子节点,就将栈内元素输出.注意存在多条路径的情况. public List<List<Integer>> pathSum(TreeNode root, int sum) { List<List<Integer>>list=new ArrayList<>(); Stack<TreeNod…
Path Sum Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example: Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 r…
Upgrade Single JAVA Component Patch Level Using SUM Tool Hi Friends, I came across few posts/threads where people are looking -How to apply patch for single component with out generating XML file in solution manager. So I thought lets write a blog on…
这是悦乐书的第169次更新,第171篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第28题(顺位题号是112).给定二叉树和整数sum,确定树是否具有根到叶路径,使得沿路径的所有值相加等于给定的sum.叶子节点是没有子节点的节点.例如: 给定以下二叉树和sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 返回true,因为存在根到叶的路径5-> 4-> 11-> 2,并且和为22. 本次解题使用的开发工具是eclips…
题目:对于任意一个树,不仅仅限于二叉树,求树中两个结点的最低公共祖先结点. 解析:对于任意一棵树,显然并不局限于二叉树,也就是说树的非叶子结点可能存在多个子节点.所以,我们可以定义两个链表结构,存储这两个结点所在的树的路径,寻找结点路径的方法可以采用前序遍历的方法,当找到两个结点所在的路径之后,我们就可以比较两个链表的各个结点,当然我们可以从后先前遍历,这样找到两条路径中的第一个相同的结点,即为我们要找的最低公共祖先,只需将该结点返回即可. class treeNode{ int value;…
Design and implement a TwoSum class. It should support the following operations: add and find. add - Add the number to an internal data structure.find - Find if there exists any pair of numbers which sum is equal to the value. For example, add(1); ad…
Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ / \ 7 2 5 1 return [ [5,4,11,2], [5,8,4,5] ] 上一道题的延伸,求出所有结果. /**…
逻辑简单,代码难写,基础不劳,leecode写注释不能出现中文,太麻烦,我写了大量注释,链表问题最重要的就是你那个指针式干啥的 提交地址https://oj.leetcode.com/problems/insertion-sort-list/ /** * Definition for singly-linked list. * public class ListNode { * int val; * ListNode next; * ListNode(int x) { * val = x; *…
一.概念和用法 左正右反 先来看看转义字符的概念:通过 \ ,?来转变后面字母或符号的含义.意思就是改变字母本身的含义. 以"\"符号为例,JAVA中有很多操作,例如文件操作等,需要用到路径这个东西,比 如:com\mypackage\xxx.xml,这个路径一般是以字符串形式表示的, 但问题来了,JAVA不知道你的\号到底是路径中的下一层的意思,还是字符串"\"的意思. 正斜杠/表示除法,分隔.在windows系统中通常用来分隔命令行参数,/表示选项等.不能作为文…
题目: Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path. Note: You can only move either down or right at any point in time. 题解: 这道题跟Unique Path系列是思路一样的.具…
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. 题解: 递归求解. 取当前点和左右边加和,当前点的值中最大的作为本层返回值.并在全局维护一个max.使用数组,因为是引用类型.所以在递归过程中可以保存结果. 代码如下:…
题目: Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example: Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 return…
题目: Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target. Note: Elements in a quadruplet (a,b,c,d) must be in non-descending or…
题目: Given an array S of n integers, are there elements a, b, c in S such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Note: Elements in a triplet (a,b,c) must be in non-descending order. (ie, a ≤ b ≤ c) The s…
题目链接:1338: The minimum square sum Description Given a prime p(p<108), you are to find min{x2+y2}, where x and y belongs to positive integer, so that x2+y2=0 (mod p). 输入一个质数 p,你找出两个正整数 x 和 y 使得 (x2+y2) mod p = 0,且 x2+y2 最小. Input Every line is a p. No…
Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in candidates where the candidate numbers sums to target. Each number in candidates may only be used once in the combination. Note: All nu…
7-1 Maximum Subsequence Sum(25 分) Given a sequence of K integers { N​1​​, N​2​​, ..., N​K​​ }. A continuous subsequence is defined to be { N​i​​, N​i+1​​, ..., N​j​​ } where 1≤i≤j≤K. The Maximum Subsequence is the continuous subsequence which has the…
Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution. Example: Given nums = [2, 7, 11, 15], target = 9, Because nums[0] + nums[1] = 2…
java.io.File.listFiles(FilenameFilter filter) 返回抽象路径名数组,表示在目录中此抽象路径名表示,满足指定过滤器的文件和目录. 声明 以下是java.io.File.listFiles(FilenameFilter filter)方法的声明: public File[] listFiles(FilenameFilter filter) 参数 filter - 文件名过滤器 返回值 该方法返回抽象路径名数组,表示在目录中此抽象路径名表示,满足指定过滤器的…
Given a collection of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. Each number in C may only be used once in the combination. Note: All numbers (including target) will be posi…
秒杀/** * Definition for binary tree * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ public class Solution { public int maxDepth(TreeNode root) { if(root==null) return 0; int h1=maxDepth(roo…
题目: Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The same repeated number may be chosen from C unlimited number of times. Note: All numbers (including target) w…
public static String readFileByUrl(String urlStr) { String res = null; try { URL url = new URL(urlStr); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //设置超时间为3秒 conn.setConnectTimeout(3 * 1000); //防止屏蔽程序抓取而返回403错误 conn.setRequest…