I-string_2019牛客暑期多校训练营（第四场）

时间限制：C/C++/Rust/Pascal 2秒，其他语言4秒
空间限制：C/C++/Rust/Pascal 512 M，其他语言1024 M
64bit IO Format: %lld

题目描述

We call $a,b$ non-equivalent if and only if $a \neq b$ and $a \neq rev(b)$ , where $rev(s)$ refers to the string obtained by reversing characters of $s$ , for example $rev(abca)=acba$ .

There is a string $s$ consisted of lower-case letters. You need to find some substrings of $s$ so that any two of them are non-equivalent. Find out what's the largest number of substrings you can choose.

输入描述:

A line containing a string  of lower-case letters.

输出描述:

A positive integer - the largest possible number of substrings of  that are non-equivalent.

示例1

输入

复制

abac

输出

复制

说明

The set of following substrings is such a choice: .

备注:

,  is consisted of lower-case letters.