main :: IO()
main = do
    str <- getLine
    print $ getsolve str
    
    
    
getsolve :: String -> Int
getsolve str
	| len == 0								= 0
    | mod len 2 == 1						= getsolve (init str)
    | (take hlen str) == (drop hlen str)	= len
    | otherwise								= getsolve (init str)
    where len = length str
          hlen = div len 2