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Day 15 - takes 2+ minutes to run and froze my computer twice but it works I guess...

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Jonathan Chan 2017-12-14 23:49:03 -08:00
parent 6a26332994
commit d378e3e50e
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import Data.Int (Int16)
gen :: Int -> Int -> Int -> [Int]
gen divisor factor seed = iterate (next divisor factor) seed
where next d f i = (f * i) `mod` d
judge :: Int -> [Int] -> [Int] -> Int
judge n a b = length . filter (uncurry eq) . take n $ zip a b
where eq i j = (fromIntegral i :: Int16) == (fromIntegral j :: Int16)
divisible :: Int -> Int -> Bool
divisible d = (== 0) . (`mod` d)
main :: IO ()
main = do
let genA = gen 2147483647 16807 634
genB = gen 2147483647 48271 301
gen4A = filter (divisible 4) genA
gen8B = filter (divisible 8) genB
print $ judge 40000000 genA genB
print $ judge 5000000 gen4A gen8B