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@@ -0,0 +1,21 @@
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+{-
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+The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
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+Find the sum of all the primes below two million.
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+-}
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+
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+is_prime :: Int -> Bool
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+is_prime x = go' x 2
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+ where
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+ go' :: Int -> Int -> Bool
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+ go' 1 y = True
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+ go' 2 y = True
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+ go' x y
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+ | x == y = True
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+ | y == 2 = if (mod x y) == 0 then False else go' x 3
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+ | otherwise = if (mod x y) == 0 then False else go' x (y+2)
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+
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+solution :: Int
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+solution = sum (filter is_prime [2..2000000])
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+
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+main :: IO ()
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+main = putStrLn ("Solution: " ++ show solution)
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