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import Data.Int
stepA :: Int64 -> Int64
stepA x = x * 16807 `mod` 2147483647
stepB :: Int64 -> Int64
stepB x = x * 48271 `mod` 2147483647
toInt16 :: Int64 -> Int16
toInt16 = fromIntegral
stepAB :: ((Int64, Int64), Int) -> ((Int64, Int64), Int)
stepAB ((x, y), n) = ((stepA x, stepB y), if (toInt16 x) == (toInt16 y) then n + 1 else n)
solve1' :: ((Int64, Int64), Int) -> Int -> ((Int64, Int64), Int)
solve1' z 0 = z
solve1' z m = let !w = stepAB z in let !m' = m - 1 in solve1' w m'
solve1 :: (Int64, Int64) -> Int
solve1 (x, y) = snd $ solve1' ((x, y), 0) 40000000
input :: (Int64, Int64)
input = (783, 325)
main = (putStrLn . show . solve1) input
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