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 回溯法 日期 题目地址:https://leetcode.com/problems/all-paths-from-source-to-target/description/ 题目描述 Given a directed, acyclic graph of N nodes. Find all possible paths from node 0 to n…

Given a directed acyclic graph (DAG) of n nodes labeled from 0 to n - 1, find all possible paths from node 0 to node n - 1 and return them in any order.The graph is given as follows: graph[i] is a list of all nodes you can visit from node i (i.e., th…

题目 https://oj.leetcode.com/problems/unique-paths/   A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below).   The robot can only move either down or right at any point in time. The robot is trying to reach the…

题目链接:https://leetcode.com/problems/all-paths-from-source-to-target/description/ Given a directed, acyclic graph of N nodes.  Find all possible paths from node 0 to node N-1, and return them in any order. The graph is given as follows:  the nodes are…

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 回溯法 日期 题目地址:https://leetcode.com/problems/unique-paths-iii/ 题目描述 On a 2-dimensional grid, there are 4 types of squares: 1 represents the starting square. There is exactly one s…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/unique-paths-ii/description/ 题目描述: A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below). The robot can only move eit…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/unique-paths/description/ 题目描述: A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below). The robot can only move either…

Unique Paths II Follow up for "Unique Paths": Now consider if some obstacles are added to the grids. How many unique paths would there be? An obstacle and empty space is marked as 1 and 0 respectively in the grid. For example, There is one obsta…

Unique Paths A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below). The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked…

题目: A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below). The robot can only move either down or right at any point in time. The robot is trying to reach the bottom-right corner of the grid (marked 'Finish'…

题目: Follow up for "Unique Paths": Now consider if some obstacles are added to the grids. How many unique paths would there be? An obstacle and empty space is marked as 1 and 0 respectively in the grid. For example, There is one obstacle in the m…

题目如下: On a 2-dimensional grid, there are 4 types of squares: 1 represents the starting square.  There is exactly one starting square. 2 represents the ending square.  There is exactly one ending square. 0 represents empty squares we can walk over. -1…

Given a directed, acyclic graph of N nodes.  Find all possible paths from node 0 to node N-1, and return them in any order. The graph is given as follows:  the nodes are 0, 1, ..., graph.length - 1.  graph[i] is a list of all nodes j for which the ed…

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 线性扫描 二分查找 日期 题目地址:https://leetcode.com/problems/find-smallest-letter-greater-than-target/description/ 题目描述 Given a list of sorted characters letters containing only lowercase l…

题目如下: You have d dice, and each die has f faces numbered 1, 2, ..., f. Return the number of possible ways (out of fd total ways) modulo 10^9 + 7 to roll the dice so the sum of the face up numbers equals target. Example 1: Input: d = 1, f = 6, target…

一天一道LeetCode (一)题目 Follow up for "Unique Paths": Now consider if some obstacles are added to the grids. How many unique paths would there be? An obstacle and empty space is marked as 1 and 0 respectively in the grid. For example, There is one ob…

[334]Increasing Triplet Subsequence (2019年2月14日,google tag)(greedy) 给了一个数组 nums,判断是否有三个数字组成子序列,使得子序列递增.题目要求time complexity: O(N),space complexity: O(1) Return true if there exists i, j, k such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k …

[94]Binary Tree Inorder Traversal [95]Unique Binary Search Trees II (2018年11月14日,算法群) 给了一个 n,返回结点是 1 - n 的所有形态的BST. 题解:枚举每个根节点 r, 然后递归的生成左右子树的所有集合,然后做笛卡尔积. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * Tr…

题目如下: On an NxN chessboard, a knight starts at the r-th row and c-th column and attempts to make exactly K moves. The rows and columns are 0 indexed, so the top-left square is (0, 0), and the bottom-right square is (N-1, N-1). A chess knight has 8 po…

目录 二分查找 排序的写法 BFS的写法 DFS的写法 回溯法 树 递归 迭代 前序遍历 中序遍历 后序遍历 构建完全二叉树 并查集 前缀树 图遍历 Dijkstra算法 Floyd-Warshall算法 Bellman-Ford算法 最小生成树 Kruskal算法 Prim算法 拓扑排序 双指针 动态规划 状态搜索 贪心 本文的目的是收集一些典型的题目,记住其写法,理解其思想,即可做到一通百通.欢迎大家提出宝贵意见! 博主有算法题解的微信公众号啦,欢迎关注「负雪明烛」,持续更新算法题的解题思路…

[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]129. Sum Root to Leaf Numbers 解题报告(Python) 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/sum-root-to-leaf-numbers/description/ 题目描述: Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a numbe…

[LeetCode]833. Find And Replace in String 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-and-replace-in-string/description/ 题目描述: To some string S, we will perform some…

[LeetCode]722. Remove Comments 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/remove-comments/description/ 题目描述: Given a C++ program, remove comments from it. The program source is an array where source[i] is the i-th line of the source…

[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]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. 递归和非递归,此提比较简单.广度优先遍历即可.关键之处就在于如何保持访问深度. 下面是4种代码: im…

Given an index k, return the kth row of the Pascal's triangle. For example, given k = 3, Return [1,3,3,1]. Note: Could you optimize your algorithm to use only O(k) extra space? 思路:最简单的方法就是依照[Leetcode]Pascal's Triangle 的方式自顶向下依次求解,但会造成空间的浪费.若仅仅用一个vect…

53. Maximum Subarray[leetcode] Find the contiguous subarray within an array (containing at least one number) which has the largest sum. For example, given the array [-2,1,-3,4,-1,2,1,-5,4],the contiguous subarray [4,-1,2,1] has the largest sum = 6. 挑…

27. Remove Element[leetcode] Given an array and a value, remove all instances of that value in place and return the new length. Do not allocate extra space for another array, you must do this in place with constant memory. The order of elements can b…

[刷题][LeetCode]总 用动画的形式呈现解LeetCode题目的思路 参考链接-空 007-整数反转 方法: 弹出和推入数字 & 溢出前进行检查 思路: 我们可以一次构建反转整数的一位数字.在这样做的时候,我们可以预先检查向原整数附加另一位数字是否会导致溢出. 算法: 反转整数的方法可以与反转字符串进行类比. 我们想重复"弹出" x 的最后一位数字,并将它"推入"到 rev 的后面.最后,rev 将与 x 相反. 要在没有辅助堆栈 / 数组的帮助下…