Skip frame increments if FrameTicks is over 1000 seconds per frame, probably indicating static at that point.
module Test where
import Control.Monad
import Data.Word
import qualified Data.IntSet as IS
data OP = Sum
| Mul
| Sub
deriving Show
genOps :: Int -> [[OP]]
genOps 1 = [[Sum], [Mul], [Sub]]
genOps n = [a : as | a <- [Sum, Mul, Sub], as <- genOps (n - 1)]
genPos :: Int -> Int -> [[Int]]
genPos m 1 = map (:[]) [-m..m - 1]
genPos m n = [a : as | a <- [-m..m - 1], as <- genPos m (n - 1)]
hash :: [Int] -> [OP] -> [Int] -> Int
hash poss op s = foldl applyOp s' (zip ss op)
where
applyOp v (n, Sum) = (v + n) `mod` 256
applyOp v (n, Mul) = (v * n) `mod` 256
applyOp v (n, Sub) = (v - n) `mod` 256
(s' : ss) = map (\p -> if p >= 0 then s !! p else s !! (l + p)) poss
l = length s
test = do
a <- liftM lines getContents
let w = minimum $ map length a
let opsNum = 4
let opsList = genOps (opsNum - 1)
let posList = genPos w opsNum
let target = length a
let wordsList = map (map fromEnum) a
let hashedSize = IS.size . IS.fromList
print $ length a
putStrLn . unlines . map show $ filter (\l -> fst l == length a) $ [(hs, (p, o)) | p <- posList, o <- opsList, let hs = hashedSize . map (hash p o) $ wordsList]
didIunderstand' = do
a <- liftM lines getContents
print $ length a
print . IS.size . IS.fromList . map (testHash . map fromEnum) $ a
where
testHash s = let l = length s in (
(s !! (l - 2) * s !! 1) + s !! (l - 1) - s !! 0
) `mod` 256