"Rafael Almeida" <[EMAIL PROTECTED]> wrote:
> perfectSquares :: [Integer]
> perfectSquares = zipWith (*) [1..] [1..]
> isPerfectSquare :: Integer -> Bool
> isPerfectSquare x = (head $ dropWhile (<x) perfectSquares) == x
what about
module Main where
isPerfectSquare :: Integer -> Bool
isPerfectSquare n = sqrrt == fromIntegral (truncate sqrrt)
where sqrrt = sqrt $ fromIntegral n
? It's a hell alot faster, but I have no idea if some numerical
property of square roots could make it give different results than your
version, in rare cases.
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