X-Git-Url: https://git.njae.me.uk/?a=blobdiff_plain;f=adventofcode1612%2Fapp%2Fadvent12.hs;fp=adventofcode1612%2Fapp%2Fadvent12.hs;h=906c1858bc25da448394bcea217d1808b18fc9cf;hb=245aed74ce202a0be5cf2f61f79b48ed51aa0e62;hp=0000000000000000000000000000000000000000;hpb=474b47bdae540d9e3e3a31a6fd9fbaf450dcc395;p=advent-of-code-16.git

diff --git a/adventofcode1612/app/advent12.hs b/adventofcode1612/app/advent12.hs
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+module Main(main) where
+
+import Text.Parsec hiding (State)
+import Text.ParserCombinators.Parsec.Number
+import Data.List (partition, union, intersect, tails)
+import Data.Char (isDigit)
+import Control.Monad.State.Lazy
+
+data Location = Literal Int | Register Char deriving (Show)
+data Instruction = Cpy Location Location | 
+                   Inc Location |
+                   Dec Location | 
+                   Jnz Location Int
+                   deriving (Show)
+
+data Machine = Machine { a :: Int
+                       , b :: Int
+                       , c :: Int
+                       , d :: Int
+                       , pc :: Int
+                       , instructions :: [Instruction]} 
+               deriving (Show)
+
+emptyMachine :: Machine
+emptyMachine = Machine {a=0, b=0, c=0, d=0, pc=0, instructions=[]}
+
+main :: IO ()
+main = do 
+    text <- readFile "data/advent12.txt" 
+    let instructions = successfulParse $ parseIfile text
+    part1 instructions
+    part2 instructions
+
+
+part1 :: [Instruction] -> IO ()
+part1 instrs = 
+    do  let m0 = emptyMachine {instructions=instrs}
+        let mf = snd $ runState runMachine m0
+        print (a mf)
+
+part2 :: [Instruction] -> IO ()
+part2 instrs = 
+    do  let m0 = emptyMachine {instructions=instrs, c=1}
+        let mf = snd $ runState runMachine m0
+        print (a mf)
+
+
+
+runMachine :: State Machine ()
+runMachine = 
+    do  m <- get
+        if (pc m) >= (length $ instructions m)
+            then return ()
+            else do executeStep
+                    runMachine
+
+executeStep :: State Machine ()
+executeStep = 
+    do  m <- get
+        let i = (instructions m)!!(pc m)
+        put (executeInstruction i m)
+
+executeInstruction :: Instruction -> Machine -> Machine
+executeInstruction (Inc (Register r)) m = m' {pc=pc1}
+    where pc1 = (pc m) + 1
+          v = evaluate m (Register r)
+          m' = writeValue m (Register r) (v+1)
+executeInstruction (Dec (Register r)) m = m' {pc=pc1}
+    where pc1 = (pc m) + 1
+          v = evaluate m (Register r)
+          m' = writeValue m (Register r) (v-1)
+executeInstruction (Cpy s d) m = m' {pc=pc1}
+    where pc1 = (pc m) + 1
+          v = evaluate m s
+          m' = writeValue m d v
+executeInstruction (Jnz s d) m 
+    | v == 0 = m {pc=pc1}
+    | otherwise = m {pc=pcj}
+    where pc1 = (pc m) + 1
+          pcj = (pc m) + d
+          v = evaluate m s
+          
+
+evaluate :: Machine -> Location -> Int
+evaluate _ (Literal i) = i
+evaluate m (Register r) = 
+    case r of
+        'a' -> (a m)
+        'b' -> (b m)
+        'c' -> (c m)
+        'd' -> (d m)
+
+writeValue :: Machine -> Location -> Int -> Machine
+writeValue m (Literal i) _ = m
+writeValue m (Register r) v =
+    case r of 
+        'a' -> m {a=v}
+        'b' -> m {b=v}
+        'c' -> m {c=v}
+        'd' -> m {d=v}
+
+
+instructionFile = instructionLine `endBy` newline 
+-- instructionLine = choice [cpyL, incL, decL, jnzL]
+instructionLine = incL <|> decL <|> cpyL <|> jnzL
+
+incL = incify <$> (string "inc" *> spaces *> (oneOf "abcd"))
+        where incify r = Inc (Register r)
+decL = decify <$> (string "dec" *> spaces *> (oneOf "abcd"))
+        where decify r = Dec (Register r)
+cpyL = cpyify <$> (string "cpy" *> spaces *> ((many1 letter) <|> (many1 digit))) 
+                  <*> (spaces *> (oneOf "abcd"))
+        where cpyify s r = Cpy (readLocation s) (Register r)
+jnzL = jnzify <$> (string "jnz" *> spaces *> ((many1 letter) <|> (many1 digit))) 
+                  <*> (spaces *> int)
+        where jnzify r d = Jnz (readLocation r) d
+
+
+readLocation :: String -> Location
+readLocation l
+    | all (isDigit) l = Literal (read l)
+    | otherwise = Register (head l)
+
+
+
+parseIfile :: String -> Either ParseError [Instruction]
+parseIfile input = parse instructionFile "(unknown)" input
+
+parseIline :: String -> Either ParseError Instruction
+parseIline input = parse instructionLine "(unknown)" input
+
+successfulParse :: Either ParseError [a] -> [a]
+successfulParse (Left _) = []
+successfulParse (Right a) = a
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