Serval loves Brain Power and his brain power problem.

Serval defines that a string $T$ is powerful iff $T$ can be obtained by concatenating some string $T'$ multiple times. Formally speaking, $T$ is powerful iff there exist a string $T'$ and an integer $k\geq 2$ such that $$T=\underbrace{T'+T'+\dots+T'}_{k\text{ times}}$$

For example, gogogo is powerful because it can be obtained by concatenating go three times, but power is not powerful.

Serval has a string $S$ consists of lowercase English letters. He is curious about the longest powerful subsequence of $S$, and he only needs you to find out the length of it. If all the non-empty subsequences of $S$ is not powerful, the answer is considered to be $0$.

A string $a$ is a subsequence of a string $b$ if $a$ can be obtained from $b$ by the deletion of several (possibly, zero or all) characters.

The first line contains a single string $S$ ($|S|\leq 80$) consisting of lowercase English letters.

Print a single integer — the length of the longest powerful subsequence of $S$. If all the non-empty subsequences of $S$ is not powerful, print $0$.