Haskell

Příklady

Načtení souboru a vypsání dat do vstupu s informací o číslu řádku

import IO
showFile f1 = do
  h1 <- openFile f1 ReadMode
  c1 <- hGetContents h1
  putStr $ unlines $ [ (show a) ++ ": " ++ b | (a,b) <- (zip [0..(length ( lines c1 ))] (lines c1) ) ]

Vytvoření binárního stromu

data Tree a = Lf 
         | Nd a (Tree a) (Tree a)
         deriving (Eq)

createTree x = Nd x Lf Lf

addTree (Nd c l r) x 
  |  x < c = if l == Lf 
        then (Nd c (createTree x) r)
        else Nd c (addTree l x) r
  | x >= c = if r == Lf 
        then Nd c l (createTree x) 
        else Nd c l (addTree r x)

array2tree [] = error "empty array"
array2tree (x:xs) = rr (createTree x) xs
  where rr tree [] = tree
        rr tree (x:xs) = rr (addTree tree x) xs

Procházení binárního stromu

inOrder Lf = []
inOrder (Nd x l r) = (inOrder l) ++ (inOrder r)

preOrder Lf = [] 
preOrder (Nd x l r) = (x:(preOrder l)) ++ (preOrder r)

postOdr Lf = [] 
postOrder (Nd x l r) = (postOrder l) ++ (postOrder r) ++ [x]