Change haskell solution to handle bigint input

2019/1/day1.hs

@@ -8,10 +8,10 @@ main = do
   printf "Part 1: %d\n" (fuel input)
   printf "Part 2: %d\n" (fuelrec input)
 
-fuel :: [Int] -> Int
+fuel :: [Integer] -> Integer
 fuel xs = sum (map (subtract 2 . (`div` 3)) xs)
 
-fuelrec :: [Int] -> Int
+fuelrec :: [Integer] -> Integer
 fuelrec xs = sum (map f xs) - sum xs where
     f x | x > 0 = x + f ((subtract 2 . (`div` 3)) x)
         | otherwise = 0