Dreamplay likes the strings that read the same upside down, that is, if we reverse the entire string, the string remains unchanged. in other words, palindrome strings
Bob does not want to upset his friend, and would thus like to make some changes, to the string P he already has, so that the string P is liked by dreamplay. Bob is allowed to make only two kinds of changes.

1. Add a character at end.
2. Replace a character.

Moreover, since Dreamplay is waiting for the string, Bob wants to do this in minimum steps.
Can you find minimum number of steps needed to change the string P such that it reads same from both ends.

Input
Only line of input consists of the string P

Output
Print a single integer, the minimum number of steps needed.

Constraints

• String P consists only of lowercase latin letters.
• \( 1 \leq length(P) \leq 5000 \)