Exercícios Haskell

exercicios.hs

import Data.List

questao1 :: Int -> [Int] -> [Int]
questao1 _ [] = []
questao1 n (x:xs)
				| ((x > n) && ((mod x 3) == 0)) = x:(questao1 n xs)
				| otherwise = questao1 n xs


questao2 :: Int -> [t] -> [t]
questao2 _ [] = []
questao2 n lista = take n lista

questao3 :: Eq t => [t] -> [t] -> [t]
questao3 lista1 lista2 = intersect lista1 lista2


is_prime :: Int -> Bool
is_prime n = if ((length [x | x <- [1 .. n], mod n x == 0]) > 2) then False else True


fat :: Int -> Int
fat 0 = 1
fat 1 = 1
fat n = n * fat (n - 1)


fib :: Int -> Int
fib 1 = 0
fib 2 = 1
fib 3 = 1
fib n = fib (n - 1) + fib (n - 2)


get_fib_numbers :: Int -> [Int]
get_fib_numbers n = [(fib x) | x <- [1 .. n]]


questao4 :: IO ()
questao4 = do
		putStr "Digite um numero: "
		num <- getLine
		if (is_prime (read num)) == True
			then do
				putStrLn ("Eh primo!" ++ " Fatorial: " ++ (show (fat (read num))) ++ "; Fibonacci: " ++ (show (get_fib_numbers (fat (read num)))))
			else do putStrLn ("Nao eh primo!" ++ " Fatorial: " ++ (show (fat (read num))) ++ "; Fibonacci: " ++ (show (get_fib_numbers (fat (read num)))))