main = do
    contents <- getContents
    let moduleMasses = map read (lines contents) :: [Int]
        initialFuel = map fuelForMass moduleMasses
        totalFuel = map fuelForFuel initialFuel
    print $ sum totalFuel

fuelForMass :: Int -> Int
fuelForMass mass = (quot mass 3) - 2

fuelForFuel :: Int -> Int
fuelForFuel mass
    | mass <= 0 = 0
    | otherwise = mass + (fuelForFuel $ fuelForMass mass)