tools/hashTest.hs
author koda
Sat, 14 Nov 2015 03:22:20 +0100
branchsdl2transition
changeset 11379 7bc9042549c1
parent 9464 901e363d5837
permissions -rw-r--r--
Drop all GLUT references It was needed to create the hidden videorec window, now SDL2 offers this feature natively.

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