31 lines
668 B
Text
31 lines
668 B
Text
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module fsieve
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import StdClass; // RWS
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import StdInt, StdReal
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NrOfPrimes :== 3000
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primes :: [Int]
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primes = pr where pr = [5 : sieve 7 4 pr]
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sieve :: Int !Int [Int] -> [Int]
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sieve g i prs
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| isPrime prs g (toInt (sqrt (toReal g))) = [g : sieve` g i prs]
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| otherwise = sieve (g + i) (6 - i) prs
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sieve` :: Int Int [Int] -> [Int]
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sieve` g i prs = sieve (g + i) (6 - i) prs
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isPrime :: [Int] !Int Int -> Bool
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isPrime [f:r] pr bd
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| f>bd = True
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| pr rem f==0 = False
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| otherwise = isPrime r pr bd
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select :: [x] Int -> x
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select [f:r] 1 = f
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select [f:r] n = select r (n - 1)
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Start :: Int
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Start = select [2, 3 : primes] NrOfPrimes
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