A. Scarborough Fair time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Are you going to Scarborough Fair? Parsley, sage, rosemary and thyme. Remember me to one who lives there. He once was th…

A. Scarborough Fair time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Are you going to Scarborough Fair? Parsley, sage, rosemary and thyme. Remember me to one who lives there. He once was th…

A. Greg and Array Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/295/problem/A Description Greg has an array a = a1, a2, ..., an and m operations. Each operation looks as: li, ri, di, (1 ≤ li ≤ ri ≤ n). To apply operation …

Codeforces Round #449 (Div. 2) https://codeforces.com/contest/897 A #include<bits/stdc++.h> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define sqr(x) ((x)*(x)) #define pb push_back #define eb emplace_back…

又掉分了0 0. A. Scarborough Fair time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Are you going to Scarborough Fair? Parsley, sage, rosemary and thyme. Remember me to one who lives there. He on…

A. Scarborough Fair 题意 对给定的长度为\(n\)的字符串进行\(m\)次操作,每次将一段区间内的某一个字符替换成另一个字符. 思路 直接模拟 Code #include <bits/stdc++.h> using namespace std; typedef long long LL; int main() { int n, m, s,t ; char c1, c2; char ss[110]; scanf("%d%d", &n, &m…

A. Saitama Destroys Hotel time limit per test:1 second memory limit per test:256 megabytes input:standard input output:standard output Saitama accidentally destroyed a hotel again. To repay the hotel company, Genos has volunteered to operate an eleva…

http://codeforces.com/contest/754/problem/D 题意: 给定几组区间,找k组区间,使得它们的公共交集最大. 思路: 在k组区间中,它们的公共交集=k组区间中右端点最小值-k组区间中左端点最大值.如果我们要区间大,那我们应该尽量让左端点小,右端点大. 先对区间按照左端点排序,然后用优先队列处理. 将区间按照左端点从小到大的顺序一一进队列,只需要进右端点即可,如果此时队列内已有k个数,则队首就是这k组区间的最小右端点,而因为左端点是从小到大的顺序进队列的,所以…

E. The Fair Nut and Strings 题目链接:https://codeforces.com/contest/1084/problem/E 题意: 输入n,k,k代表一共有长度为n的多少个字符串.然后给出一个最小字符串s,最大字符串t,满足对于所有的k个字符串有s<=S<=t. 最后求满足条件的k个字符串(自己构造)的不同前缀数量的和. 题解: 这题很巧妙,设dp(i)表示长度为i的前缀的数量和,一开始有dp(1)=0. 后来随着长度的增加,我们每次可以在最后加一个a或者b,…

D. The Fair Nut and the Best Path 题目链接:https://codeforces.com/contest/1084/problem/D 题意: 给出一棵树,走不重复的路径,每到一个结点加上其权值,经过一条边减去其权值,路径中途减去后不能出现负数,问怎么选择路径可以让最后得到的最大. 题解: 这题考虑用dp来做. 我们定义dp[u]为走到u点的最大值,注意这里的方向,是走到u点.题目中的意思是路径不能走回头路. 对于一个父节点u,那么我们可以根据走到其儿子结点的最…

C. The Fair Nut and String 题目链接:https://codeforces.com/contest/1084/problem/C 题意: 给出一个字符串,找出都为a的子序列(比如ai,aj,ak)满足以下条件的个数: 1.子序列的索引单增(i<j<k): 2.在原字符串中,若ai=aj=ak=a,那么满足i<=k1<j,j<=k2<k 并且 ak1=ak2=b. 通俗点说,就是找这样的子序列个数:要么单个a,要么每个a之间都至少有一个b. 题解…

D. The Fair Nut and the Best Path 题意:给出一张图 点有权值 边也要权值 从任意点出发到任意点结束 到每个点的时候都可以获得每个点的权值,而从边走的时候都要消耗改边的边权,如果当前值小于边的边权,就走不通,问从任意点出发到任意点结束的可以获得的最大权多少(其中到一个点结束的时候也能获得改点的值) 思路:一个很明显的树上dp的问题 \(dp[i]\)表示以i为起点的可以获得的最高的权值是多少 \(dp[i]=w[i]+max(son(dp[j]))\) 其中j为i…

B. Chtholly's request time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output — Thanks a lot for today. — I experienced so many great things. — You gave me memories like dreams... But I have to le…

题目链接 交互题. 题意:给你三个数n,m,k.让你完成至多m次互动,每次给你一个q,让你从n个位置选一个位置放这个数,覆盖已经放过的数.让你再m次使得n个位置的数不递减,达到直接退出. 解法:暴力,如果q小于c/2的话,从前往后找,若当前位置没有数或者比q大的话,就直接放再这个位置上,大于c/2的话就从后往前找,若当前位置没有数或者比q小的话就直接放. 如果每个位置都有数的话说明放完了. #include<bits/stdc++.h> #define LL long long #define…

B:注意到nc/2<=m,于是以c/2为界决定数放在左边还是右边,保证序列满足性质的前提下替换掉一个数使得其更靠近边界即可. #include<iostream> #include<cstdio> #include<cmath> #include<cstdlib> #include<cstring> #include<algorithm> using namespace std; #define ll long long #de…

题意 给你一个长为 \(n\) 的序列 \(a_i\) 需要支持四个操作. \(1~l~r~x:\) 把 \(i \in [l, r]\) 的 \(a_i\) 加 \(x\) . \(2~l~r~x:\) 把 \(i \in [l, r]\) 的 \(a_i\) 赋值成 \(x\) . \(3~l~r~x:\) 求 \([l, r]\) 区间的第 \(x\) 小元素. \(4~l~r~x~y:\) 求 \((\sum_{i = l}^{r} {a_i}^x) \mod y\) . 一共会操作 \…

ODT(主要特征就是推平一段区间) 其实就是用set来维护三元组,因为数据随机所以可以证明复杂度不超过O(NlogN),其他的都是暴力维护 主要操作是split,把区间分成两个,用lowerbound, 有两点需要注意1.set里的东西不能改,所以变成了mutable(可改的const),2.s.insert返回pair类型,first是插入点的迭代器 = =sort里的比较函数ll没开wa了好久 精简版: //#pragma comment(linker, "/stack:200000000&…

C. Nephren gives a riddle time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output What are you doing at the end of the world? Are you busy? Will you save us? Nephren is playing a game with little…

D. One-Dimensional Battle ShipsTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/567/problem/D Description Alice and Bob love playing one-dimensional battle ships. They play on the field in the form of a line consisting of n …

D. A and B and Interesting Substrings time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A and B are preparing themselves for programming contests. After several years of doing sports program…

B. Hamming Distance Sum time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Genos needs your help. He was asked to solve the following programming problem by Saitama: The length of some string…

->链接在此<- B. Kefa and Company time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Kefa wants to celebrate his first big salary by going to restaurant. However, he needs company. Kefa has n fri…

B. Amr and The Large Array time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Amr has got a large array of size n. Amr doesn't like large arrays so he intends to make it smaller. Amr doesn't c…

Codeforces Round #485 (Div. 2) D. Fair 题目连接: http://codeforces.com/contest/987/problem/D Description Some company is going to hold a fair in Byteland. There are $n$ towns in Byteland and $m$ two-way roads between towns. Of course, you can reach any t…

Codeforces Round #436 (Div. 2) 敲出一身冷汗...感觉自己宛如智障:( codeforces 864 A. Fair Game[水] 题意:已知n为偶数,有n张卡片,每张卡片上都写有一个数,两个人每人选一个数,每人可以拿的卡片必须写有是自己选的数,问能否选择两个数使得两个人每人拿的卡片数一样多并且能拿光卡片.[就是看输入是不是只有两种数字] //:第一遍我看成字符串包含有选的数字也能拿,,这样写着居然过了..水题水题.. #include<cstdio> #inc…

Codeforces Round #272 (Div. 2) A. Dreamoon and Stairs time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Dreamoon wants to climb up a stair of n steps. He can climb 1 or 2 steps at each move.…

Codeforces Round #366 (Div. 2) A I hate that I love that I hate it水题 #I hate that I love that I hate it n = int(raw_input()) s = "" a = ["I hate that ","I love that ", "I hate it","I love it"] for i in ran…

Codeforces Round #354 (Div. 2) Problems     # Name     A Nicholas and Permutation standard input/output 1 s, 256 MB    x3384 B Pyramid of Glasses standard input/output 1 s, 256 MB    x1462 C Vasya and String standard input/output 1 s, 256 MB    x1393…

直达–>Codeforces Round #368 (Div. 2) A Brain’s Photos 给你一个NxM的矩阵,一个字母代表一种颜色,如果有”C”,”M”,”Y”三种中任意一种就输出”#Color”,如果只有”G”,”B”,”W”就输出”#Black&White”. #include <cstdio> #include <cstring> using namespace std; const int maxn = 200; const int INF =…

 cf之路,1,Codeforces Round #345 (Div. 2) ps:昨天第一次参加cf比赛,比赛之前为了熟悉下cf比赛题目的难度.所以做了round#345连试试水的深浅.....       其实这个应该是昨天就写完的,不过没时间了,就留到了今天.. 地址:http://codeforces.com/contest/651/problem/A A. Joysticks time limit per test 1 second memory limit per test 256…