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25 lines
635 B
Haskell
25 lines
635 B
Haskell
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{-
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If p is the perimeter of a right angle triangle with integral length sides, {a,b,c}, there are exactly three solutions for p = 120.
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{20,48,52}, {24,45,51}, {30,40,50}
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For which value of p 1000, is the number of solutions maximised?
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-}
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import Data.List
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import Data.Ord
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import Text.Printf
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import Util.Triangle
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trimap = do
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let totals = map (\x -> (x, (length . triangles) x)) [1..999]
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last (sortBy (comparing snd) totals)
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triangles sum = do
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let cs = reverse (takeWhile (<= sum - 3) [3..])
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concat (map (\x -> right_triangles sum x) cs)
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main = do
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printf "Maximum triangles found with sum = %d\n" (fst trimap)
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