advent of code 2020 day 18 part1

import Prelude hiding ((+), (*))
import qualified Prelude as P

infixl 6 +, *

main :: IO ()
main = print $ sum expr


(+) x y = x P.+ y
(*) x y = x P.* y

expr = [ 2 * 3 + (4 * 5)
       , 5 + (8 * 3 + 9 + 3 * 4 * 3)
       , 5 * 9 * (7 * 3 * 3 + 9 * 3 + (8 + 6 * 4))
       , ((2 + 4 * 9) * (6 + 9 * 8 + 6) + 6) + 2 + 4 * 2]