import Control.Monad
import Control.Applicative

solver :: [Int] -> Int
solver [] = 0
solver xs =
    let ys  = filter even xs
        ys' = map (\x -> x `div` 2) ys
        in length ys' + solver ys'

main :: IO ()
main = do
    _ <- getLine
    s <- (map read) . words <$> getLine
    print $ solver s
