29 lines
634 B
Haskell
29 lines
634 B
Haskell
module SolaveyStrassen (solaveyStrassen) where
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import ModularArithmeticUtils (modExp, jacobi)
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import System.Random (randomRIO)
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solaveyStrassen :: Integer -> Integer -> IO Bool
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solaveyStrassen n k
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| n < 2 = return False
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| n == 2 = return True
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| even n = return False
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| otherwise = go k
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where
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expHalf = (n - 1) `div` 2
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go 0 = return True
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go i = do
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a <- randomRIO (2, n - 2)
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if gcd a n /= 1
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then return False
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else do
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let x = modExp a expHalf n
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j = jacobi a n `mod` n
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if x /= j
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then return False
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else go (i - 1)
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