Codeforces Round 207 (Div. 1)
E
Xenia and String Problem
Codeforces
3000
原题
← D→
翻译中…

Xenia the coder went to The Olympiad of Informatics and got a string problem. Unfortunately, Xenia isn't fabulous in string algorithms. Help her solve the problem.

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String $*s*$ is a sequence of characters $*s*_{1}*s*_{2}... *s*_{|*s*|}$, where record $|*s*|$ shows the length of the string.

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Substring $*s*[*i*... *j*]$ of string $*s*$ is string $*s*_{*i*}*s*_{*i* + 1}... *s*_{*j*}$.

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String $*s*$ is a Gray string, if it meets the conditions:

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  • the length of string $|*s*|$ is odd;
  • character image occurs exactly once in the string;
  • either $|*s*| = 1$, or substrings image and image are the same and are Gray strings.
翻译中…

For example, strings "abacaba", "xzx", "g" are Gray strings and strings "aaa", "xz", "abaxcbc" are not.

翻译中…

The beauty of string $*p*$ is the sum of the squares of the lengths of all substrings of string $*p*$ that are Gray strings. In other words, consider all pairs of values $*i*, *j*$ $(1 ≤ *i* ≤ *j* ≤ |*p*|)$. If substring $*p*[*i*... *j*]$ is a Gray string, you should add $(*j* - *i* + 1)^{2}$ to the beauty.

翻译中…

Xenia has got string $*t*$ consisting of lowercase English letters. She is allowed to replace at most one letter of the string by any other English letter. The task is to get a string of maximum beauty.

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Input

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The first line contains a non-empty string $*t*$ $(1 ≤ |*t*| ≤ 10^{5})$. String $*t*$ only consists of lowercase English letters.

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Output

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Print the sought maximum beauty value Xenia can get.

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Please do not use the %lld specifier to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specifier.

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Note

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In the first test sample the given string can be transformed into string $*p*$ = "zbz". Such string contains Gray strings as substrings $*p*[1... 1]$, $*p*[2... 2]$, $*p*[3... 3]$ и $*p*[1... 3]$. In total, the beauty of string $*p*$ gets equal to $1^{2} + 1^{2} + 1^{2} + 3^{2} = 12$. You can't obtain a more beautiful string.

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In the second test case it is not necessary to perform any operation. The initial string has the maximum possible beauty.

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样例

Input #1
zzz
Output #1
12
InputCopy OutputCopy
Input #2
aba
Output #2
12
InputCopy OutputCopy
Input #3
abacaba
Output #3
83
InputCopy OutputCopy
Input #4
aaaaaa
Output #4
15
InputCopy OutputCopy
题目信息
题号
356E
时间限制
1 s
内存限制
256 MB
标签
动态规划
哈希
模拟
后缀结构
字符串

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