Content 给定一个长度为 \(n\) 的数列 \(\{a_i\}_{i=1}^n\),请找出在数列中仅出现一次的最小的数的位置. 数据范围:\(t\) 组询问,\(1\leqslant t\leqslant 10^4,1\leqslant a_i\leqslant n\leqslant 2\times 10^5,\sum n\leqslant 2\times10^5\). Solution 边输入边统计这些信息: 这个数出现的次数. 这个数出现的位置. 所有数的最小值. 所有数的最大值.…

前言   [LeetCode 题解]系列传送门:  http://www.cnblogs.com/double-win/category/573499.html   1.题目描述 There are N gas stations along a circular route, where the amount of gas at station i is gas[i]. You have a car with an unlimited gas tank and it costs cost[i]…

Unique Paths II 题解 原创文章,拒绝转载 题目来源:https://leetcode.com/problems/unique-paths-ii/description/ Description 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 e…

判别MST是否唯一的例题. POJ1679-The Unique MST 题意:给定图,求MST(最小生成树)是否唯一,唯一输出路径长,否则输出Not Unique! 题解:MST是否唯一取决于是否有两边权值相同(其中一条边在第一次求得的MST内,另一条在MST外)的情况. 如果存在这样的边,则需要逐次删除MST内的该边,再次求MST,如果此次求得的MST路长与第一次MST相同,则确实存在不唯一的MST 否则,一定不存在多条MST. //Kruskal-判断MST是否唯一 //Time:0MS…

传送门 D. Drazil and Tiles time limit per test 2 seconds memory limit per test 256 megabytes Drazil created a following problem about putting 1 × 2 tiles into an n × m grid: "There is a grid with some cells that are empty and some cells that are occupie…

DFS基础 深度优先搜索(Depth First Search)是一种搜索思路,相比广度优先搜索(BFS),DFS对每一个分枝路径深入到不能再深入为止,其应用于树/图的遍历.嵌套关系处理.回溯等,可以用递归.堆栈(stack)实现DFS过程. 关于广度优先搜索(BFS)详见:算法与数据结构基础 - 广度优先搜索(BFS) 关于递归(Recursion)详见:算法与数据结构基础 - 递归(Recursion) 树的遍历 DFS常用于二叉树的遍历,关于二叉树详见: 算法与数据结构基础 - 二叉查找树…

Contest 111 (题号941-944)(2019年1月19日,补充题解,主要是943题) 链接:https://leetcode.com/contest/weekly-contest-111 [941]Valid Mountain Array(第一题 3分)(google tag) 判断一个数组是不是 Mountain 数组. Mountain 数组的定义是 A.length >= 3There exists some i with 0 < i < A.length - 1 su…

题目来源 https://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 bott…

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   思路: 遇到二叉树,多半是分为左右子树两个问题递归下去. 由序列[1,…,m]和[i+1,…

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' in t…