题目要求符合以下条件的最大的d 化简得 注意到 最多只有2*sqrt(a[i]-1)种取值,也就是一共最多有n*sqrt(10^19)种取值,于是枚举一下d,计算出符合上上式的最大的d更新答案,然后d跳跃到下一个取值 效率O(n²sqrt(10^9)) #include<bits/stdc++.h> #define ll long long using namespace std; ,inf=1e9; ll n,k,ans,r; ll a[maxn]; void read(ll &k)…

显然是不可能交叉取钥匙的,于是把钥匙和人都按坐标排序就可以DP了 钥匙可以不被取,于是f[i][j]表示前i个钥匙被j个人拿的时间 f[i][j]=min(f[i-1][j],max(f[i-1][j-1],abs(b[i]-a[j])+abs(P-b[i])); #include<bits/stdc++.h> #define ll long long using namespace std; ,inf=2e9; int n,k,p; ],f[maxn*][maxn]; void read(i…

Codeforces Round #423 (Div. 1, rated, based on VK Cup Finals) A.String Reconstruction B. High Load C. DNA Evolution 题意:给定一个只包含A,T,C,G的字符串S,有如下两种操作 1)修改一个点的字母. 2)给定一个字符串e ($\left | e \right |\leq 10$),生成一个由e重复组成的新串,eee...,问$S_{l..r}$中有几个字母跟这个新的字符串一一对应…

E. DNA Evolution 题目连接: http://codeforces.com/contest/828/problem/E Description Everyone knows that DNA strands consist of nucleotides. There are four types of nucleotides: "A", "T", "G", "C". A DNA strand is a seque…

Everyone knows that DNA strands consist of nucleotides. There are four types of nucleotides: "A", "T", "G", "C". A DNA strand is a sequence of nucleotides. Scientists decided to track evolution of a rare species, wh…

昨晚一个瓜皮说今晚有cf,听说是晚间场,我瞅了一眼,娃,VK Cup,上分的好机会,看着比赛时间就有点心酸了,0:35,当时一直在纠结要不要打的问题,当时想着应该不难吧,要不打一下吧,要不还是看看题先,如果容易就打,难的话就不打了好的吧!于是就这样愉快的决定了.......cf日常延时10分钟,0:45,要不要去睡觉啊,干脆先睡一觉好了,然后又是忍不住诱惑在等待开始! 比赛一开始,瞅了一眼A,这不是一道水题嘛,直接敲啊,然后1分钟就搞定了,交了就过了,B题直接求边界点就好了,扫了一遍就过了,C题…

http://codeforces.com/contest/831 A. Unimodal Array time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Array of integers is unimodal, if: it is strictly increasing in the beginning; after that…

A:链接:http://codeforces.com/contest/831/problem/A 解题思路: 从前往后分别统计递增,相等,递减序列的长度,如果最后长度和原序列长度相等那么就输出yes: 实现代码: #include<bits/stdc++.h> using namespace std; int main() { ,a[]; cin>>m; ;i<m;i++){ cin>>a[i]; } ;i<m-;i++){ ]) ans++; else b…

题目传送门 传送门I 传送门II 传送门III 题目大意 求一个满足$d\sum_{i = 1}^{n} \left \lceil \frac{a_i}{d} \right \rceil - \sum_{i = 1}^{n} a_{i} \leqslant K$的最大正整数$d$. 整理一下可以得到条件是$d\sum_{i = 1}^{n} \left \lceil \frac{a_i}{d} \right \rceil \leqslant K + \sum_{i = 1}^{n} a_{i}$…

There are n people and k keys on a straight line. Every person wants to get to the office which is located on the line as well. To do that, he needs to reach some point with a key, take the key and then go to the office. Once a key is taken by somebo…