Codeforces Round 396 (Div. 2)
C
Mahmoud and a Message
Codeforces
1700
原题
← BD →
翻译中…

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 $*a*_{*i*}$. For example, if $*a*_{1} = 2$ 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.

翻译中…

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 $*a*_{1} = 2$ 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.

翻译中…

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.

翻译中…

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:

翻译中…
  • 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 $10^{9} + 7$.
  • 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?
翻译中…

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".

翻译中…

Input

翻译中…

The first line contains an integer $*n*$ ($1 ≤ *n* ≤ 10^{3}$) denoting the length of the message.

翻译中…

The second line contains the message $*s*$ of length $*n*$ that consists of lowercase English letters.

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The third line contains $26$ integers $*a*_{1}, *a*_{2}, ..., *a*_{26}$ ($1 ≤ *a*_{*x*} ≤ 10^{3}$) — the maximum lengths of substring each letter can appear in.

翻译中…

Output

翻译中…

Print three lines.

翻译中…

In the first line print the number of ways to split the message into substrings and fulfill the conditions mentioned in the problem modulo $10^{9}  +  7$.

翻译中…

In the second line print the length of the longest substring over all the ways.

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In the third line print the minimum number of substrings over all the ways.

翻译中…

Note

翻译中…

In the first example the three ways to split the message are:

翻译中…
  • a|a|b
  • aa|b
  • a|ab
翻译中…

The longest substrings are "aa" and "ab" of length $2$.

翻译中…

The minimum number of substrings is $2$ in "a|ab" or "aa|b".

翻译中…

Notice that "aab" is not a possible splitting because the letter 'a' appears in a substring of length $3$, while $*a*_{1} = 2$.

翻译中…

样例

Input #1
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
Output #1
3
2
2
InputCopy OutputCopy
Input #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
Output #2
401
4
3
InputCopy OutputCopy
题目信息
题号
766C
时间限制
2 s
内存限制
256 MB
标签
暴力
动态规划
贪心
字符串

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。