Codeforces Round #396 (Div. 2) C
Mahmoud wrote a message s of length n. He wants to send it as a birthday present to his friend Moaz who likes strings. He wrote it on a magical paper but he was surprised because some characters disappeared while writing the string. That's because this magical paper doesn't allow character number i in the English alphabet to be written on it in a string of length more than ai. For example, if a1 = 2 he can't write character 'a' on this paper in a string of length 3 or more. String "aa" is allowed while string "aaa" is not.
Mahmoud decided to split the message into some non-empty substrings so that he can write every substring on an independent magical paper and fulfill the condition. The sum of their lengths should be n and they shouldn't overlap. For example, if a1 = 2 and he wants to send string "aaa", he can split it into "a" and "aa" and use 2 magical papers, or into "a", "a" and "a" and use 3 magical papers. He can't split it into "aa" and "aa" because the sum of their lengths is greater than n. He can split the message into single string if it fulfills the conditions.
A substring of string s is a string that consists of some consecutive characters from string s, strings "ab", "abc" and "b" are substrings of string "abc", while strings "acb" and "ac" are not. Any string is a substring of itself.
While Mahmoud was thinking of how to split the message, Ehab told him that there are many ways to split it. After that Mahmoud asked you three questions:
- How many ways are there to split the string into substrings such that every substring fulfills the condition of the magical paper, the sum of their lengths is n and they don't overlap? Compute the answer modulo 109 + 7.
- What is the maximum length of a substring that can appear in some valid splitting?
- What is the minimum number of substrings the message can be spit in?
Two ways are considered different, if the sets of split positions differ. For example, splitting "aa|a" and "a|aa" are considered different splittings of message "aaa".
The first line contains an integer n (1 ≤ n ≤ 103) denoting the length of the message.
The second line contains the message s of length n that consists of lowercase English letters.
The third line contains 26 integers a1, a2, ..., a26 (1 ≤ ax ≤ 103) — the maximum lengths of substring each letter can appear in.
Print three lines.
In the first line print the number of ways to split the message into substrings and fulfill the conditions mentioned in the problem modulo 109 + 7.
In the second line print the length of the longest substring over all the ways.
In the third line print the minimum number of substrings over all the ways.
3
aab
2 3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
3
2
2
10
abcdeabcde
5 5 5 5 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
401
4
3
In the first example the three ways to split the message are:
- a|a|b
- aa|b
- a|ab
The longest substrings are "aa" and "ab" of length 2.
The minimum number of substrings is 2 in "a|ab" or "aa|b".
Notice that "aab" is not a possible splitting because the letter 'a' appears in a substring of length 3, while a1 = 2.
题意:说的是字符串分割,不过是有条件的,一个字符在一个分割区域是不能出现超过ai次,问能分几次,每个区间最长多少,最短多少
解法:
1 dp[i]表示到第i位置能分割多少次,和它前i-j的位置有关,j<=i(表示能分割的长度)i-j+1是距离i有j个长度的地方(在i的左边)
2 每次讨论j都需要验证是不是满足条件,是的话就是+dp[i-j]
3 最长的距离当然是比较j喽,最短的话比较Min[i-j]+1和Min[i]
#include<bits/stdc++.h>
using namespace std;
int n;
char s[];
int mod=1e9+;
long long dp[];
long long a[];
long long Min[];
int solve(int x,int y,int len){
int Len=len;
for(int i=x;i<=y;i++){
if(Len>a[s[i]-'a']){
return ;
}
}
return ;
}
int main(){
cin>>n;
cin>>s+;
for(int i=;i<;i++){
cin>>a[i];
}
dp[]=;
int maxn=;
for(int i=;i<=n;i++){
Min[i]=1e9;
for(int j=;j<=i;j++){
if(solve(i-j+,i,j)){
dp[i]+=(dp[i-j]%mod);
dp[i]%=mod;
maxn=max(j,maxn);
Min[i]=min(Min[i-j]+,Min[i]);
}
}
}
cout<<dp[n]%mod<<endl;
cout<<maxn<<endl;
cout<<Min[n]<<endl;
return ;
}
Codeforces Round #396 (Div. 2) C的更多相关文章
- Codeforces Round #396 (Div. 2) D. Mahmoud and a Dictionary 并查集
D. Mahmoud and a Dictionary 题目连接: http://codeforces.com/contest/766/problem/D Description Mahmoud wa ...
- Codeforces Round #396 (Div. 2) A,B,C,D,E
A. Mahmoud and Longest Uncommon Subsequence time limit per test 2 seconds memory limit per test 256 ...
- Codeforces Round #396 (Div. 2) A B C D 水 trick dp 并查集
A. Mahmoud and Longest Uncommon Subsequence time limit per test 2 seconds memory limit per test 256 ...
- Codeforces Round #396 (Div. 2) D. Mahmoud and a Dictionary
地址:http://codeforces.com/contest/766/problem/D 题目: D. Mahmoud and a Dictionary time limit per test 4 ...
- Codeforces Round #396 (Div. 2) D
Mahmoud wants to write a new dictionary that contains n words and relations between them. There are ...
- Codeforces Round #396 (Div. 2) E. Mahmoud and a xor trip dfs 按位考虑
E. Mahmoud and a xor trip 题目连接: http://codeforces.com/contest/766/problem/E Description Mahmoud and ...
- Codeforces Round #396 (Div. 2) C. Mahmoud and a Message dp
C. Mahmoud and a Message 题目连接: http://codeforces.com/contest/766/problem/C Description Mahmoud wrote ...
- Codeforces Round #396 (Div. 2) B. Mahmoud and a Triangle 贪心
B. Mahmoud and a Triangle 题目连接: http://codeforces.com/contest/766/problem/B Description Mahmoud has ...
- Codeforces Round #396 (Div. 2) A. Mahmoud and Longest Uncommon Subsequence 水题
A. Mahmoud and Longest Uncommon Subsequence 题目连接: http://codeforces.com/contest/766/problem/A Descri ...
- Codeforces Round #396 (Div. 2) E. Mahmoud and a xor trip
地址:http://codeforces.com/contest/766/problem/E 题目: E. Mahmoud and a xor trip time limit per test 2 s ...
随机推荐
- bzoj4485: [Jsoi2015]圈地
思维僵化选手在线被虐 其实应该是不难的,题目明显分成两个集合,要求是不同集合的点不能联通 先假设全选了,然后二分图最小割,相邻两个点直接连墙的费用就可以了 #include<cstdio> ...
- Java版本更新历史(ing)
历史版本特性 JDK Version 1.0 开发代号为Oak(橡树),于1996-01-23发行. JDK Version 1.1 于1997-02-19发行. 引入的新特性包括: 引入JDBC(J ...
- springmvc配置一:ajax请求防止返回中文乱码配置说明
Spring3.0 MVC @ResponseBody 的作用是把返回值直接写到HTTP response body里. Spring使用AnnotationMethodHandlerAdapter的 ...
- NHibernate从入门到精通系列——NHibernate环境与结构体系
内容摘要 NHibernate的开发环境 NHibernate的结构体系 NHibernate的配置 一.NHibernate的开发环境 NHibernate的英文官方网站为:http://nhfor ...
- 怎样通过计算机ip地址访问sql server 2008数据库
在设置外网访问SQL2008数据库之前,首先必须保证局域网内访问SQL2008没有问题 .那么,我们先来看看局域网内访问SQL2008数据库需要哪些步骤和设置,才能做到在局域网内任何一台机器上输入 ...
- 抓屏工具 faststone capture
百度百科 http://baike.baidu.com/link?url=te51CfOKYIEmqT1jsyRwcB8Pnals5xQ8nUXk6trvBPGSJRBO5G7BEZL7cYQxmx8 ...
- HDOJ-1280
前m大的数 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)Total Submi ...
- E - Jolly Jumpers
E - Jolly Jumpers Time Limit:3000MS Memory Limit:0KB 64bit IO Format:%lld & %llu Submit ...
- 技术胖Flutter第三季-18布局CardWidget 卡片布局组件
技术胖Flutter第三季-18布局CardWidget 卡片布局组件 博客地址: https://jspang.com/post/flutter3.html#toc-420 最外面是Card布局,里 ...
- Flutter实战视频-移动电商-46.详细页_自定义TabBar Widget
46.详细页_自定义TabBar Widget 主要实现详情和评论的tab provide定义变量 自己做一个tab然后用provide去控制 定义两个变量来判断是左侧选中了还是右侧选中了.并定义一个 ...