20150325.hs

type Key = Int
type Objeto = (Key,String)
type HashTable = [Objeto]

baseTable :: HashTable
baseTable = []

initTable:: HashTable->Int-> HashTable
initTable ht sz | sz == 100  = ht
				| otherwise  = initTable ((-1,""):ht) (sz+1)


hash::Int->Int->Int
hash k m = (k) `mod` m

checkNext :: Int->Int->HashTable->Int
checkNext k v ht| k == (fst (ht!!v)) = v
				| (hash k 100) == v = -1
				| otherwise = checkNext k ((v+1) `mod` 100) ht


get:: Key->HashTable->String
get	k ht | k == (fst (ht!!v)) = (snd (ht!!v))
		 | (checkNext k (v+1) ht) == -1 = "key invalida"
		 | otherwise = snd (ht!!(checkNext k (v+1) ht))
			where v = ((hash k 100))

nextAvailabe:: Int->Int->Int->HashTable->Int
nextAvailabe k v e h | -1 == (fst (h!!v)) || k == (fst (h!!v))= v
				     | v == e = -1
				     | otherwise  = (nextAvailabe k ((v+1) `mod` 100) e h)

put:: Key->String->HashTable->HashTable
put k s ht | -1 == (fst (ht!!mk)) || k ==(fst (ht!!mk))  = (take (mk) ht) ++ (k,s):(drop (mk+1) ht)
		   | nb == -1 = ht
		   | otherwise =  (take (nb) ht) ++ (k,s):(drop (nb+1) ht)
		 where	mk = ((hash k 100))
		 	nb = (nextAvailabe k (mk+1) mk ht)
		   			  
remove::Key->HashTable->HashTable
remove k ht | k == (fst (ht!!v)) = (take (v) ht) ++ (-1,""):(drop (v+1) ht) 
			| (checkNext k (v+1) ht) == -1 = ht
			| otherwise = (take (na) ht) ++ (-1,""):(drop (na+1) ht)
			where v = (hash k 100)
			      na = (checkNext k (v+1) ht)

hasKey:: Key->HashTable->Bool
hasKey k [] = False
hasKey k (x:xs) | k==(fst x) =True
				| otherwise = (hasKey k xs)

-------------CONJUNTOS

haveElement :: (Eq t)=>t->[t]->Bool
haveElement a [] = False;
haveElement a (s:xs) | a==s = True
				   | otherwise = haveElement a xs

contem:: (Eq t) => [t]->[t]->Bool
contem a [] = True
contem a (b:xb) = (haveElement b a) && (contem a xb)

intersecta:: (Eq t) => [t]->[t]->Bool
intersecta a [] = False
intersecta a (b:xb) = (haveElement b a) || (intersecta a xb)

comparaConjuntos ::(Eq t) => [t]->[t] ->String
comparaConjuntos a b 	| cab && cba = "A igual B"
					 	| cab = "A contem B"
					 	| cba = "B contem A"
					 	| iab = "A interseciona B"
					 	| otherwise = "Conjuntos Disjuntos"
							where	cab = (contem a b)
								cba = (contem b a)
								iab = (intersecta a b)