题意:有一个字符串和一组数,可以对字符串删去任意字符后为数组的长度,且可以随意排序,要求修改后的字符串的每个位置上的字符满足:其余大于它的字符的位置减去当前位置绝对值之和等于对应序列位置上的数. 题解:贪心,我们发现,数组中\(0\)的位置一定对应字符串中最大的字符,所以我们从这个位置来构造,我循环来找,每次找数组中为\(0\)的位置,然后记录字符,对其他没有取过的位置减去为\(0\)的位置,每次都这样搞就行了.具体的还是看代码吧,每一步都应该听清晰的. 代码: #include <iostre…

Codeforces 题面传送门 & 洛谷题面传送门 一道名副其实的 hot tea 首先显然可以发现这俩人在玩 Nim 游戏,因此对于一个 \(c_i\in[l,r]\) 其 SG 值就是 \(c_i-l\),最终游戏的 SG 值就是 \(\oplus_{c_i\in[l,r]}(c_i-l)\),如果该值为 \(0\) 答案就是 B,否则答案是 A. 从这一步开始就有好几种不同复杂度的做法了,下面将一一介绍它们. 下视 \(n,m,q\) 同阶. 做法一:暴力 迫真 · \(2\times…

E. A Simple Task Problem's Link: http://codeforces.com/problemset/problem/558/E Mean: 给定一个字符串,有q次操作,每次操作将(l,r)内的字符升序或降序排列,输出q次操作后的字符串. analyse: 基本思想是计数排序. 所谓计数排序,是对一个元素分布较集中的数字集群进行排序的算法,时间复杂度为O(n),但使用条件很苛刻.首先对n个数扫一遍,映射出每个数字出现的次数,然后再O(n)扫一遍处理出:对于数字ai,…

题目链接:http://codeforces.com/contest/70/problem/D Once a walrus professor Plato asked his programming students to perform the following practical task. The students had to implement such a data structure that would support a convex hull on some set of…

Problem D"Decoding Task" Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100002 Description In the near future any research and publications about cryptography are outlawed throughout the world on the grounds of national se…

题目链接:http://codeforces.com/contest/558/problem/E E. A Simple Task time limit per test5 seconds memory limit per test512 megabytes inputstandard input outputstandard output   This task is very simple. Given a string S of length n and q queries each qu…

E. A Simple Task 题目连接: http://www.codeforces.com/contest/558/problem/E Description This task is very simple. Given a string S of length n and q queries each query is on the format i j k which means sort the substring consisting of the characters from…

引子: A题过于简单导致不敢提交,拖拖拉拉10多分钟还是决定交,太冲动交错了CE一发,我就知道又要错过一次涨分的机会.... B题还是过了,根据题意目测数组大小开1e5,居然蒙对,感觉用vector更好一点... C题WA第9组,GG思密达....明天起床再补C吧 - - 题目链接: http://codeforces.com/contest/835/problem/B B. The number on the board Some natural number was written on t…

B. Nanami's Digital Board 题目连接: http://www.codeforces.com/contest/434/problem/B Description Nanami is an expert at playing games. This day, Nanami's good friend Hajime invited her to watch a game of baseball. Unwilling as she was, she followed him to…

题目链接: http://codeforces.com/problemset/problem/558/E E. A Simple Task time limit per test5 secondsmemory limit per test512 megabytes 问题描述 This task is very simple. Given a string S of length n and q queries each query is on the format i j k which mea…