A9508. Kolya and Tandem Repeat
编程题
普及/提高-
知识点
题目描述
Kolya got string $s$ for his birthday, the string consists of small English letters. He immediately added $k$ more characters to the right of the string.
Then Borya came and said that the new string contained a tandem repeat of length $l$ as a substring. How large could $l$ be?
See notes for definition of a tandem repeat.
Then Borya came and said that the new string contained a tandem repeat of length $l$ as a substring. How large could $l$ be?
See notes for definition of a tandem repeat.
输入格式
The first line contains $s$ ( $1<=|s|<=200$ ). This string contains only small English letters. The second line contains number $k$ ( $1<=k<=200$ ) — the number of the added characters.
输出格式
Print a single number — the maximum length of the tandem repeat that could have occurred in the new string.
输入输出样例
输入 #1
aaba 2
输出 #1
6
输入 #2
aaabbbb 2
输出 #2
6
输入 #3
abracadabra 10
输出 #3
20
说明/提示
A tandem repeat of length $2n$ is string $s$ , where for any position $i$ ( $1<=i<=n$ ) the following condition fulfills: $s_{i}=s_{i+n}$ .
In the first sample Kolya could obtain a string aabaab, in the second — aaabbbbbb, in the third — abracadabrabracadabra.
In the first sample Kolya could obtain a string aabaab, in the second — aaabbbbbb, in the third — abracadabrabracadabra.