AoC2019/day5.hs

import Data.List.Split
import Data.Char as Char

main = do
    let state = [3,0,4,0,99]
    let input = [83]
    let output = operation state state 0 input []  
    mapM putStrLn (map show output)

getList :: String -> [Int]
getList = map read . splitOn ","

changeInput :: [Int] -> Int -> Int -> [Int]
changeInput (begin:_:_:input) input1 input2= [begin] ++ [input1] ++ [input2] ++ input

func :: [Int] -> Int -> Int -> Int
func xs x y = do
	let input = changeInput xs x y
        head (compute input input 0 [] [] )	

compute :: [Int] -> [Int] -> Int -> [Int] -> [Int] -> [Int]
compute (99:_) state index input output = output
compute (op:x:y:z:_) state index input output= 
        compute (drop newindex state) newstate newindex input output 
        where
	    sum = if op == 1 then
                  (state !! x) + (state !! y)
	          else 
                 (state !! x) * (state !! y)
            split = splitAt z state
            newstate = (fst split) ++ [sum] ++ (drop 1 (snd split))
            newindex = index + 4

operation :: [Int] -> [Int] -> Int -> [Int] -> [Int] -> [Int]
operation (99:_) state index input output = 
	output
operation (op:x:y:z:_) state index input output 
  | last (digits op) == 1 = 
	  operation (drop newindex state) newstate newindex input output
          where 
		  newindex = index + 4
                  newstate = add (fillup (revertdigs op) 5) x y z state
  | last (digits op) == 2 = 
	  operation (drop newindex state) newstate newindex input output
          where 
		  newindex = index + 4
                  newstate = mult (fillup (revertdigs op) 5) x y z state
  | last (digits op) == 3 =
	  operation (drop newindex state) newstate newindex newinput output
          where
		  newindex = index + 2
                  newstate = input (fillup (revertdigs op) 3) x (head input) state
                  newinput = drop 1 input  
  | last (digits op) == 4 =
	  operation (drop newindex state) state newindex input newoutput
          where
		  newindex = index + 2
                  newoutput = log (fillup (revertdigs op) 3) ouput x state
                  newinput = drop 1 input  


add :: [Int] -> Int -> Int -> Int -> [Int] -> [Int]
add (op1:op2:m1:m2:m3) p1 p2 p3 state = 
	 insert state sum index 
	 where
		sum = (getValue m1 p1 )  + (getValue m2 p2)
                index = getValue m3 p3

mult :: [Int] -> Int -> Int -> Int -> [Int] -> [Int]
mult (op1:op2:m1:m2:m3) p1 p2 p3 state = 
	 insert state sum index 
	 where
		sum = (getValue m1 p1 ) * (getValue m2 p2)
                index = getValue m3 p3

input :: [Int] -> Int -> Int -> [Int] -> [Int]
input(op1:op2:m1) p1 input state =
         insert state input (getValue m1 p1)

log :: [Int] -> [Int] -> Int -> [Int] -> [Int]
log (op1:op2:m1) output p1 state =
	output ++ [(state !! (getValue m1 p1))]

insert ::  [Int] -> Int -> Int -> [Int]
insert xs value index = do
                let split = splitAt index xs
                (fst split)++ [value] ++ (drop 1 (snd split))

digits :: Int -> [Int]
digits = map Char.digitToInt . show

revertdigs :: Int -> [Int]
digs 0 = []
digs x = x `mod` 10 : digs (x `div` 10)

fillup :: [Int] -> Int -> [Int]
fillup array x = x ++ (replicate (x - (length array)) 0)

getValue :: Int -> Int -> [Int] -> Int
getValue 0 index array = array !! index
getValue 1 index array = index