D2. Kirk and a Binary String (hard version) time limit per test1 second memory limit per test256 megabytes inputstandard input outputstandard output The only difference between easy and hard versions is the length of the string. You can hack this pro…

题意:https://codeforc.es/problemset/problem/1204/D2 给你一个01串,如:0111001100111011101000,让你改这个串(使0尽可能多,任意 l~r 的LIS最长上升子序列长度不变). 问:0111001100111011101000 答:0011001100001011101000 思路: 参考题解:考虑什么串无法该变. 1. 10无法被改变(我们称为固定串),00,01,11都可以改. 2. 固定串+固定串(无法被改变). 3. 1+…

题目大意 两个人轮流在一个字符串上删掉一个字符,没有字符可删的人输掉游戏 删字符的规则如下: 1. 每次从一个字符串中选取一个字符,它是一个长度至少为 3 的奇回文串的中心 2. 删掉该字符,同时,他选择的那个字符串分成了两个独立的字符串 现在问,先手是否必胜,如果先手必胜,输出第一步应该删掉第几个字符,有多解的话,输出序号最小的那个 字符串的长度不超过5000,只包含小写英文字母 做法分析 可以这样考虑:将所有的长度大于等于 3(其实只需要找长度为 3 的就行)的奇回文串的中心标记出来 我们将…

Codeforces Round #297 (Div. 2)B. Pasha and String Time Limit: 2 Sec  Memory Limit: 256 MBSubmit: xxx  Solved: 2xx 题目连接 http://codeforces.com/contest/525/problem/B Description Pasha got a very beautiful string s for his birthday, the string consists o…

题目传送门 /* 题意:给出m个位置,每次把[p,len-p+1]内的字符子串反转,输出最后的结果 字符串处理:朴素的方法超时,想到结果要么是反转要么没有反转,所以记录 每个转换的次数,把每次要反转的反转就不超时了:) */ #include <cstdio> #include <algorithm> #include <cstring> using namespace std; ; const int INF = 0x3f3f3f3f; char s[MAXN]; i…

题目传送门 /* 题意:找到一个字符串p,使得它和s,t的不同的总个数相同 贪心:假设p与s相同,奇偶变换赋值,当是偶数,则有答案 */ #include <cstdio> #include <algorithm> #include <cstring> #include <cmath> #include <iostream> using namespace std; ; const int INF = 0x3f3f3f3f; int p[MAXN…

B2. Character Swap (Hard Version) This problem is different from the easy version. In this version Ujan makes at most 2…

Codeforces Round #622 (Div. 2) C2. Skyscrapers (hard version) 题意: 你是一名建筑工程师,现给出 n 幢建筑的预计建设高度,你想建成峰状,如: 1 2 3 2 1 → 1 2 3 2 1 1 2 3 1 2 → 1 2 3 1 1 8 10 6 → 8 10 6 10 6 8 → 10 6 6 问所有建筑的高度和最大为多少. 思路: 单调递增栈栈顶存储以当前点为峰的单侧最低高度下标,另存储以每个点为峰的左右最大高度和. #includ…

半个月没看cf 手生了很多(手动大哭) Problem - A - Codeforces 题意 给定数字n, 求出最大数字k, 使得  n & (n−1) & (n−2) & (n−3) & ... (k) = 0 题解 &:有0则0 假如n转为二进制共有x位 , 要使&后=0, k的最高位需=0 我们使最高位=0,后面都为1; 那么此数+1=什么 =100000(x-1个0), 这样就能&后=0了 -------------------------…

D1. RGB Substring (easy version) time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output The only difference between easy and hard versions is the size of the input. You are given a string s consistin…

https://codeforces.com/contest/1118/problem/D2 和easy version的主要区别是,数据增加了. easy version采用的是线性查找,效率低 在这里采用binary search就可以了 #include<bits/stdc++.h> using namespace std; int n,m; vector<int> num; int C(int d){ ; ;i<n;i++){ sum+=max(num[i]-i/d,…

A. Water Buying 链接:http://codeforces.com/contest/1118/problem/A 实现代码: #include<bits/stdc++.h> using namespace std; #define ll long long int main() { ll n,a,b,m; cin>>n; ;i <= n;i ++){ cin>>m>>a>>b; <= b) cout<<m*a…

(easy version): 题目链接:http://codeforces.com/contest/1296/problem/E1 题目一句话就是说,两种颜色不同的字符可以相互换位, 问,对这字符串用最多两种颜色染色,然后经过有限次换位 可以变成字典序排序的顺序. 思路:一个字符需不需要换位,应该是参照最后的字典序的顺序, 那么,我们应该给字符串排序,再去思考问题. 我们知道,如果str[now_i]的位置和排序后的位置不一样,那就是需要换位. 我们还知道,如果str[now_i]的当前位置如…

题目链接: C1. Skyscrapers (easy version) 题目描述: 有一行数,使得整个序列满足 先递增在递减(或者只递增,或者只递减) ,每个位置上的数可以改变,但是最大不能超过原来的值. 最后找到满足这样的序列并且满足 这种方案 所有数加起来 和 是最大的. 考察点 : 贪心,对数据范围的掌握程度,计算每次加数时有可能会 爆 int 析题得侃: 比赛的时候看到这道题直接找了 最大值,然后以最大值为中心向两侧递减,交了一发, WA 后来想到可能会有重复的最大值,因为每个值并不是…

This problem is different from the easy version. In this version Ujan makes at most 2n2n swaps. In addition, k≤1000,n≤50k≤1000,n≤50 and it is necessary to print swaps themselves. You can hack this problem if you solve it. But you can hack the previou…

C. Vasya and String 题目连接: http://www.codeforces.com/contest/676/problem/C Description High school student Vasya got a string of length n as a birthday present. This string consists of letters 'a' and 'b' only. Vasya denotes beauty of the string as th…

B. Equidistant String Time Limit: 20 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/545/problem/B Description Little Susie loves strings. Today she calculates distances between them. As Susie is a small girl after all, her strings conta…

任意门:http://codeforces.com/contest/1118/problem/F1 F1. Tree Cutting (Easy Version) time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given an undirected tree of nn vertices. Some vert…

任意门:http://codeforces.com/contest/1118/problem/D1 D1. Coffee and Coursework (Easy version) time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output The only difference between easy and hard versions…

在每个给出的子串的起始位置打个标记,记录的是从这里开始的最长子串. 然后输出的时候就扫,如果遇到开始位置,就从这里开始输出,如果其后被更长的覆盖,就跳转到更长的串进行输出. 如果位置没被覆盖,就输出'a'. #include<cstdio> #include<string> #include<algorithm> #include<iostream> using namespace std; string s[100010]; int n,m,p[20000…

F1. Pictures with Kittens (easy version) 题目链接:https://codeforces.com/contest/1077/problem/F1 题意: 给出n个数,以及k,x,k即长度为k的区间至少选一个,x的意思是一共要选x个,少一个或者多一个都不行. 选一个会得到一定的奖励,问在满足条件的前提下,最多得到多少的奖励. 题解: 简单版本数据量比较小,考虑比较暴力的动态规划. dp[i,j]表示前i个数,要选第i个数,目前选了j个所得到的最大奖励,那么当…

#include<bits/stdc++.h>using namespace std;const int maxn=1e6+7;pair<string,int>p[maxn];int nn,n;int cmp(pair<string,int>a,pair<string,int>b){    return a.first.length()<b.first.length();}char ans[maxn];multiset<string>sst…

C. Vasya and String time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output High school student Vasya got a string of length n as a birthday present. This string consists of letters 'a' and 'b' onl…

B1. Character Swap (Easy Version) This problem is different from the hard version. In this version Ujan makes exactly one exchange. You can hack this problem only if you solve both problems. After struggling and failing many times, Ujan decided to tr…

D2. RGB Substring (hard version) inputstandard input outputstandard output The only difference between easy and hard versions is the size of the input. You are given a string…

传送门:http://codeforces.com/contest/1092/problem/D2 D2. Great Vova Wall (Version 2) time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Vova's family is building the Great Vova Wall (named by Vo…

D2. Optimal Subsequences (Hard Version) This is the harder version of the problem. In this version, 1≤n,m≤2⋅105. You can hack this problem if you locked it. But you can hack the previous problem only if you locked both problems. You are given a seque…

D2. The World Is Just a Programming Task (Hard Version) This is a harder version of the problem. In this version,…

D. Binary String Minimizing You are given a binary string of length n (i. e. a string consisting of n characters '0' and '1'). In one move you can swap two adjacent characters of the string. What is the lexicographically minimum possible string you c…

You are given a binary string of length nn (i. e. a string consisting of nn characters '0' and '1'). In one move you can swap two adjacent characters of the string. What is the lexicographically minimum possible string you can obtain from the given o…