Day2New

type Student = (String, Int)
s1 :: Student
s2 :: Student
s1 = ("Kiro Stamatov", 111213)
s2 = ("Hristo Hristov", 102030)

mult4 :: (Int, Int, Int, Int) -> Int
mult4 (x, y, z, t) = x*y*z*t

sort2 :: (Int, Int) -> (Int, Int)
sort2 (x, y) = if x >= y then (x, y) else (y, x)

fib :: Int -> Int
fib n
    | n == 1 = 1
    | n == 2 = 1
    | n > 2  = fib (n-2) + fib (n-1)
    | otherwise = error "Not defined"

fibStep :: (Int, Int) -> (Int, Int)
fibStep (u, v) = (u, u+v)


fibPair :: Int -> (Int, Int)
fibPair n = (fib(n), fib(n + 1))

toEnd :: a -> [a] -> [a]
toEnd x l = l ++ [x]

sumPairs :: [(Int, Int)] -> [Int]
sumPairs pL = [x + y | (x, y) <- pL]

digit :: Char -> Bool
digit ch = ch >= '0' && ch <= '9'

all_digits :: String -> String
all_digits str = [ch | ch <- str,  digit ch]

allEven :: [Int] -> Bool
allEven x = (x == [a | a <- x, even a])

allOdd :: [Int] -> Bool
allOdd x = (x == [a | a <- x, odd a])

revWords :: String -> String
revWords input = (unwords . reverse . words) input

sumMy :: [Int] -> Int
sumMy [] = 0
sumMy (x:xs) = x + sum xs

concatMy :: [[a]] -> [a]
concatMy [] = []
concatMy (x : xs) = x ++ concat xs

sumList :: [Int] -> Int
sumList [] = 0
sumList (x:xs) = x + sumList xs

concatList :: [[a]] -> [a]
concatList [] = []
concatList (x : xs) = x ++ concatList xs

member :: Int -> [Int] -> Bool
member x [] = False
member x (y:ys) = (x == y) || (member x ys)

plus1 :: [Int] -> [Int]
plus1 [] = []
plus1 (x:xs) = x + 1 : plus1 xs

filterEven :: [Int] -> [Int]
filterEven [] = []
filterEven (x:xs)
    | even x    = x : filterEven xs
    | otherwise = filterEven xs


filterMy :: (Int -> Bool) -> [Int] -> [Int]
filterMy p [] = []
filterMy p (x:xs)
    | p x       = x : filterMy p xs
    | otherwise = filterMy p xs

insert :: Int -> [Int] -> [Int]
insert x [] = [x]
insert x (y:ys)
    | x <= y = x : (y:ys)
    | otherwise = y : insert x ys

insertSort :: [Int] -> [Int]
insertSort [] = []
insertSort (x:xs) = insert x (insertSort xs)