hide complete IP of other users, when non-admin requests player info. showing the first two parts of the IP was kinda pointless to begin with (what for?) and has recently lead to increased abuse and lobby flooding due to bots collecting/posting IP tracking information
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