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24 lines
756 B
Haskell
24 lines
756 B
Haskell
{- Find the only Pythagorean triplet, {a, b, c}, for which a + b + c = 1000.
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A Pythagorean triplet is a set of three natural numbers, a b c, for which,
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a2 + b2 = c2
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For example, 32 + 42 = 9 + 16 = 25 = 52.
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There exists exactly one Pythagorean triplet for which a + b + c = 1000.
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Find the product abc.
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-}
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import Text.Printf
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import Util.Triangle
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-- |Return the product of the sides of the first triangle having the sum of the sides 'sum'
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triplet :: Int -> Int
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triplet sum = do
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let cs = reverse (takeWhile (<= sum - 3) [3,5..])
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let tri = head (concat (map (\x -> right_triangles sum x) cs))
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let (Triangle a b c) = tri
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a * b * c
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main = do
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printf "Pythagorean triplet product having a + b + c = 1000: %d\n" (triplet 1000 :: Int)
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