In dieser Aufgabe beschäftigen wir uns mit den Standarlisten in Haskell.
> module Listen where
> import Data.List
> import Data.Ratio
> data Li a = E | a :> Li a deriving (Show,Eq)
> infixr 5 :>
> laengeLi E = 0
> laengeLi (_:>xs) = 1 + laengeLi xs
> laenge [] = 0
> laenge (_:xs) = 1 + laenge xs
> letzteLi (x:>E) = x
> letzteLi (_:>xs) = letzteLi xs
> letzte1 (x:[]) = x
> letzte1 (_:xs) = letzte1 xs
> letzte2 [x] = x
> letzte2 (_:xs) = letzte2 xs
> istSortiertLi (x1:>x2:>xs)
> |x1<=x2 = istSortiertLi (x2:>xs)
> |otherwise = False
> istSortiertLi _ = True
> istSortiert (x1:x2:xs)
> |x1<=x2 = istSortiert (x2:xs)
> |otherwise = False
> istSortiert _ = True
> istSortiert2 (x1:ys@(x2:xs))
> |x1<=x2 = istSortiert2 ys
> |otherwise = False
> istSortiert2 _ = True
> wiederholeLi x = x:>wiederholeLi x
> wiederhole x = x:wiederhole x
> factorial1 n = product [1,2..n]
> factorial2 n = product$take n [1,2..]
> isPalindrome :: Eq a => [a] -> Bool
> isPalindrome xs = False
> everyNth :: Integral a => a -> [b] -> [b]
> everyNth _ _ = []
> swapNeighbours :: [a] -> [a]
> swapNeighbours xs = xs
> maxRep :: Eq a => [a] -> Int
> maxRep _ = 0
> leibniz:: [Rational]
> leibniz = [k {-- ToDo --}|k<-[0,1..]]
> fatio:: [Rational]
> fatio = [k {-- ToDo --}|k<-[0,1..]]
> squaresum :: (Foldable t, Num a, Functor t) => t a -> a
> squaresum xs = 0
> sqx :: (Fractional a, Foldable t, Functor t) => t a -> a
> sqx xs = 0 -- Todo
> where
> l x = fromIntegral $ length x
> mittelwerte :: (Fractional a, Enum a) => [a] -> [a]
> mittelwerte xs = [] --ToDo
> readBinary:: String -> Integer
> readBinary xs = aux 0 xs
> where
> aux result xs = result
> toOctalString :: (Show a, Integral a) => a -> String
> toOctalString x = ""
> occurrences :: (Num a, Eq t) => [t] -> [(a, t)]
> occurrences _ = [] --ToDo
> anagram :: Eq a => [a] -> [[a]]
> anagram xs = [] --ToDo
Subato
