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…

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…

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…

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…

[LeetCode]732. My Calendar III解题报告 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/my-calendar-iii/description/ 题目描述: Implement a MyCalendarThree class to store your events. A new event can always be added. Your class will have one method, book…

[LeetCode]95. Unique Binary Search Trees 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/unique-binary-search-trees-ii/description/ 题目描述: Given an integer n, generate all s…

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 repre…

一天一道LeetCode系列 (一)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…

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…

Difficulty:easy  More:[目录]LeetCode Java实现 Description Design and implement a TwoSum class. It should support the following operations: addand find.add(input) – Add the number input to an internal data structure.find(value) – Find if there exists any…

原题链接在这里:https://leetcode.com/problems/unique-paths-iii/ 题目: 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 s…

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 repre…

Combination Sum III Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascend…

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 + DFS BFS + DFS 日期 题目地址:https://leetcode.com/problems/path-sum-iii/#/description 题目描述 You are given a binary tree in which each node contains an integer value. Find the num…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址: https://leetcode.com/problems/unique-substrings-in-wraparound-string/description/ 题目描述: Consider the string s to be the infinite wraparound string of "abcdefghijklmnopqrstuvwxyz", so…

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 方法一:DFS 方法二:回溯法 日期 题目地址:https://leetcode.com/problems/combination-sum-iii/description/ 题目描述: Find all possible combinations of k numbers that add up to a number n, given that…

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 记忆化递归 动态规划 卡特兰数 日期 题目地址:https://leetcode.com/problems/unique-binary-search-trees/description/ 题目描述 Given n, how many structurally unique BST's (binary search trees) that store…

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…

Unique Binary Search Trees II Given n, generate all structurally unique BST's (binary search trees) that store values 1...n. For example,Given n = 3, your program should return all 5 unique BST's shown below. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \…

Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3 Tree Dynamic Programming   Solution 1:  递归 clas…

problem 437. Path Sum III 参考 1. Leetcode_437. Path Sum III; 完…

题目来源: https://leetcode.com/problems/unique-paths-iii/ 自我感觉难度/真实难度: 题意: 分析: 回溯法,直接DFS就可以了 自己的代码: class Solution: def uniquePathsIII(self, grid: List[List[int]]) -> int: res=0 n=len(grid) m=len(grid[0]) for i in range(n): for j in range(m): if grid[i][…

Unique Binary Search Trees Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3 Base case: n==0, n==…

Unique Morse Code Words Description International Morse Code defines a standard encoding where each letter is mapped to a series of dots and dashes, as follows: "a" maps to ".-", "b" maps to "-...", "c" ma…

Consider the string s to be the infinite wraparound string of "abcdefghijklmnopqrstuvwxyz", so s will look like this: "...zabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcd....". Now we have another string p. Your job is to find…