构造题都是神仙题 /kk ARC066C Addition and Subtraction Hard 首先要发现两个性质: 加号右边不会有括号:显然,有括号也可以被删去,答案不变. \(op_i\)和\(A_{i+1}\)之间只会有一个括号:有多个括号的话只保留最外边那个,答案不变. 然后就可以定义状态:\(dp_{i,j}\)表示前\(i\)个数,还有\(j\)个未闭合的左括号,得到的最大答案. 由于只有减号右边有括号,所以只要知道左边有几个未闭合的左括号,就可以知道自己的贡献是\(1\)还是…

[arc073f]Many Moves(动态规划,线段树) 题面 atcoder 洛谷 题解 设\(f[i][j]\)表示第一个棋子在\(i\),第二个棋子在\(j\)的最小移动代价. 发现在一次移动结束之后,总是有一个棋子会动到当前位置,因此状态改为当前是第\(i\)次操作,第\(i\)次操作没有动的那个棋子在\(j\)位置时的最小代价. 把第一维省掉,用线段树动态维护这个数组. 每次枚举移动哪一个棋子,直接线段树对应修改即可. #include<iostream> #include<…

题目 一个显然的\(dp\),设\(dp_{i,j}\)表示其中一个棋子在\(x_i\)点,另一个棋子在\(j\)点的最小花费 显然\(dp_{i,j}\)有两种转移 第一种是把\(x_i\)上的棋子移到\(x_{i+1}\),那么那么就是\(dp_{i+1,j}=\min(dp_{i,j}+|x_{i+1}-x_i|)\) 第二种就是把\(j\)上的棋子移动到\(x_{i+1}\),那么就是\(dp_{i+1,x_i}=\min(dp_{i,j}+|j-x_{i+1}|)\) 这是\(O(nQ…

[atcoder contest 010] F - Tree Game Time limit : 2sec / Memory limit : 256MB Score : 1600 points Problem Statement There is a tree with N vertices, numbered 1 through N. The i-th of the N−1 edges connects vertices ai and bi. Currently, there are Ai s…

总的来说,这次的题目比较水,然而菜菜的我并没有把所有题目都做完,话不多说,直接来干货: A:Next Alphabet 题目链接:https://atcoder.jp/contests/abc151/tasks/abc151_a 题目描述:Given is a lowercase English letter C that is not z. Print the letter that follows C in alphabetical order. 大致解读:给你一个小写字母,输出这个小写字母…

Given a non-empty integer array, find the minimum number of moves required to make all array elements equal, where a move is incrementing a selected element by 1 or decrementing a selected element by 1. You may assume the array's length is at most 10…

Given a non-empty integer array of size n, find the minimum number of moves required to make all array elements equal, where a move is incrementing n - 1 elements by 1. Example: Input: [1,2,3] Output: 3 Explanation: Only three moves are needed (remem…

原题链接在这里:https://leetcode.com/problems/minimum-moves-to-equal-array-elements-ii/ 题目: Given a non-empty integer array, find the minimum number of moves required to make all array elements equal, where a move is incrementing a selected element by 1 or d…

原题链接在这里:https://leetcode.com/problems/minimum-moves-to-equal-array-elements/ 题目: Given a non-empty integer array of size n, find the minimum number of moves required to make all array elements equal, where a move is incrementing n - 1 elements by 1.…

Problem: Given a non-empty integer array of size n, find the minimum number of moves required to make all array elements equal, where a move is incrementing n - 1 elements by 1. Example: Input: [1,2,3] Output: 3 Explanation: Only three moves are need…