Problem Statement

Moriya-chan the ant is abnormally obsessed with line symmetry.
One day, Moriya-chan resolved to eliminate everything in this world that is not line-symmetric.
So, to begin with, she decided to practice an operation that makes a string line-symmetric.
The operation is as follows.

• You are given a string S consisting only of half-width alphanumeric characters.
• Delete some characters of S to make it a line-symmetric string. However, deleting a character does not close the gap (it becomes a space), and deleted characters are not counted in the string length.
• Make the length of the string after the operation as long as possible.
• Assume that there are infinitely many spaces before and after the given string.
• Spaces are not counted in the string length.

• a  s  a

  is a "palindrome" and its "character positions are symmetric", so it is line-symmetric, and its length is 3.

• i l l

  has "character positions that are symmetric" but is not a "palindrome", so it is not line-symmetric.

• ut u

  is a "palindrome" but its "character positions are not symmetric", so it is not line-symmetric.

Input

S

\( |S| \leq 1000 \)

Output

Output the longest possible length of the string resulting from applying the operation to S.

Sample

chiwawa

3

abracadabra

5

1145141919810

5