Primer Parcial 1er Cuat 2006 (Paradigmas)

Ejercicio 1

locate::String->String->Nat
locate s c = foldr (\t r1 -> if (t==c) then 1+r1 else r1) 0 s

transpose::String->String->String
transpose s1 s2 s3 = foldr (\c r1 -> (s1 !! (locate s2 c)) : r1) [] s3

Ejercicio 2

• a)

primFoldBinTree::(BinTree a->BinTree a->a->b->b->b)->b->BinTree a->b
primFoldBinTree f z Nil = z
primFoldBinTree f z (Bin n i d) = f i d n (primFoldBinTree f z i) (primFoldBinTree f z d)

• b)

foldBinTree::(a->b->b->b)->b->BinTree a->b
foldBinTree g z a = primFoldBinTree (\a1 a2 n r1 r2 -> g n r1 r2) z a

• c)

elemSearchTree::Ord a=>a->SearchTree a->Bool
elemSearchTree e a = foldBinTree (\n x1 x2 -> if n==e then true else if n>e then x1 else x2) false a

• d)

insertSearchTree::Ord a=>a->SearchTree a->SearchTree a
insertSearchTree e a = primFoldBinTree (\i d n ri rd -> if e>=n then Branch n i rd) else (Branch n ri d)) (Branch e Nil Nil) a