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…

题意跟某道我出的等差子序列求最值非常像…… 反正询问的长度只有10种,你就建立10批树状数组,每组的公差是确定的,首项不同. 然后询问的时候只需要枚举询问串的每一位,找找这一位对应哪棵树状数组即可. 修改的时候会在10棵树状数组里修改,也是算算修改的位置对应哪一棵即可. 要注意,一共有4种字符,每个树状数组其实分成4个,就只需要单点修改,维护前缀和了…… #include<cstdio> #include<cstring> using namespace std; int n,m,…

DNA Evolution 题目让我们联想到树状数组或者线段树,但是如果像普通那样子统计一段的和,空间会爆炸. 所以我们想怎样可以表示一段区间的字符串. 学习一发大佬的解法. 开一个C[10][10][4][n],就可以啦,第二维表示e的长度,第一维表示i%e的长度,第三维表示颜色,第四维求和了. #include <bits/stdc++.h> using namespace std; ; char s[maxn]; map<char,int> mp; ][][][maxn];…

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…

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…

D. High Load 题目连接: http://codeforces.com/contest/828/problem/D Description Arkady needs your help again! This time he decided to build his own high-speed Internet exchange point. It should consist of n nodes connected with minimum possible number of…

C. String Reconstruction 题目连接: http://codeforces.com/contest/828/problem/C Description Ivan had string s consisting of small English letters. However, his friend Julia decided to make fun of him and hid the string s. Ivan preferred making a new strin…

A.题目链接:http://codeforces.com/contest/828/problem/A 解题思路: 直接暴力模拟 #include<bits/stdc++.h> using namespace std; int main() { ,ans=,a[]; cin>>m>>d>>s; ;i<m;i++){ cin>>a[i]; &&d) d--; &&d==&&s){ s--;num+…

Arkady needs your help again! This time he decided to build his own high-speed Internet exchange point. It should consist of n nodes connected with minimum possible number of wires into one network (a wire directly connects two nodes). Exactly k of t…

Ivan had string s consisting of small English letters. However, his friend Julia decided to make fun of him and hid the string s. Ivan preferred making a new string to finding the old one. Ivan knows some information about the string s. Namely, he re…