http://projecteuler.net/index.php?section=problems&id=25 -- Haskell, 090104 import List (findIndex) import Maybe (fromJust) import Sequence (fibonacci) main = print $ (+) 1 $ fromJust $ findIndex ((<=) 1000 . length . show) fibonacci 数列…

-- Haskell, 090105 module Prime (prime, isprime) where -- 素数 prime :: Integral a => [a] prime = 2 : filter (\n -> (all (\x -> n`mod`x/=0) . takeWhile (\x -> x*x<=n)) prime) [3..] -- 素数判定 isprime :: Integral a => a -> Bool isprime n =…

-- Haskell, 090104 module Sequence (prime, fibonacci, factorial, trianglar) where import qualified Prime (prime) -- 素数 prime = Prime.prime -- フィボナッチ数 fibonacci :: Integral a => [a] fibonacci = 1 : 1 : zipWith (+) fibonacci (tail f…