tools/hashTest.hs
author unc0rr
Wed, 02 May 2018 23:07:41 +0200
changeset 13358 a79c1206bacd
parent 9464 901e363d5837
permissions -rw-r--r--
Call GetNext twice as many times to distribute seed across the whole buffer even for single byte seeds

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