Lab2_PF

--Exercitiul 1
poly2 :: Double -> Double -> Double -> Double -> Double

poly2 x a b c = a * x * x + b * x + c


--Exercitiul 2
eeny :: Integer -> String
eeny x
    | even x    = "eeny"
    | otherwise = "meeny"


--Exercitiul 3
fizzbuzz :: Integer -> String
fizzbuzz x
    | x `mod` 15 == 0 = "FizzBuzz"
    | x `mod` 3 == 0  = "Fizz"
    | x `mod` 5 == 0  = "Buzz"
    | otherwise     = ""

fizzbuzz' :: Integer -> String
fizzbuzz' x = if(mod x 15 == 0) then "FizzBuzz"
                else if(mod x 3 == 0) then "Fizz"
                else if(mod x 5 == 0) then "Buzz"
                else ""


fibonacciCazuri :: Integer -> Integer
fibonacciCazuri n
    | n < 2     = n
    | otherwise = fibonacciCazuri (n - 1) + fibonacciCazuri (n - 2)


fibonacciEcuational :: Integer -> Integer
fibonacciEcuational 0 = 0
fibonacciEcuational 1 = 1
fibonacciEcuational n =
    fibonacciEcuational (n - 1) + fibonacciEcuational (n - 2)

 
tribonacciCazuri :: Integer -> Integer
tribonacciCazuri n
    | n < 1               = 0
    | n <= 2 && n >= 1    = 1
    | otherwise = tribonacciCazuri(n-1) + tribonacciCazuri(n-2) + tribonacciCazuri(n-3)

tribonacciEcuational :: Integer -> Integer
tribonacciEcuational 0 = 0
tribonacciEcuational 1 = 1
tribonacciEcuational 2 = 1
tribonacciEcuational 3 = 2
tribonacciEcuational n = tribonacciEcuational(n-1) +tribonacciEcuational(n-2) +tribonacciEcuational(n-3)


binomial :: Integer -> Integer -> Integer
binomial n k
    | k == 0    = 1
    | n == 0    = 0
    | otherwise = (binomial (n - 1) k) + (binomial (n - 1) (k - 1))


verifL :: [Int] -> Bool
verifL v
    | mod (length v) 2 == 0 = True
    | otherwise             = False


takefinal :: [a] -> Int -> [a]
takefinal v n
    | (length v) <= n   = v
    | otherwise         = drop ((length v) - n) v

remove :: [Int] -> Int -> [Int]
remove v n = concat[(take (n - 1) v), (drop (n) v)]


-- semiPareRec [0,2,1,7,8,56,17,18] == [0,1,4,28,9]
semiPareRec :: [Int] -> [Int]
semiPareRec [] = []
semiPareRec (h:t)
 | even h    = h `div` 2 : t'
 | otherwise = t'
 where t' = semiPareRec t

myreplicate :: Int -> a -> [a]
myreplicate n v
    | n == 0    = []
    | otherwise = v:myreplicate (n - 1) v

sumImp :: [Int] -> Int 
sumImp [] = 0
sumImp (h:t)
    | mod h 2 == 1  = h + t'
    | otherwise     = t'
    where t' = sumImp t

totalLen :: [String] -> Int
totalLen [] = 0
totalLen (h:t)
    | take 1 h == "A"   = (length h) + t'
    | otherwise         = t'
    where t' = totalLen t