P8781 [AtCoder] AtCoder Beginner Contest 066 - ss
入门
题目描述

We will call a string that can be obtained by concatenating two equal strings an even string. For example, xyzxyz and aaaaaa are even, while ababab and xyzxy are not.

You are given an even string S consisting of lowercase English letters. Find the length of the longest even string that can be obtained by deleting one or more characters from the end of S. It is guaranteed that such a non-empty string exists for a given input.

Constraints

  • $2 \leq |S| \leq 200$
  • S is an even string consisting of lowercase English letters.
  • There exists a non-empty even string that can be obtained by deleting one or more characters from the end of S.

Input

Input is given from Standard Input in the following format:

S

Output

Print the length of the longest even string that can be obtained.

Examples

Input

abaababaab

Output

6

Input

xxxx

Output

2

Input

abcabcabcabc

Output

6

Input

akasakaakasakasakaakas

Output

14

输入格式

见题面

输出格式

见题面

样例输入
abaababaab
样例输出
6