Hello! Can anybody point me to a right way here? I have those exercises in haskell that i cannot do, because haskell is so much different from other languages that i use. I have read so much from different manuals but i do not understand haskell enough yet. First exercise: I must find a shorter list. Here's how i did that, but my teacher said that it is unefficient way to do it. getShorter :: [a] -> [a] -> [a] getShorter xs ys | length xs <= length ys = xs | otherwise = ys How do i do it effective, so that i only check as many elements from lists as many are in the shortest list? Second exercise: Second exercise also need an effective answer: I have to remove any occurances of certain number from list and give the number of how many times that number was removed. Unefficient version: remCount :: Int -> [Int] -> (Int,[Int]) remCount n xs = (length xs - length ys, ys) where ys = [ x | x <- xs, x /= n] Exercise three: moneyBack :: Int -> [(Int,Int)] I must print out all pairs of bank notes and (bank notes, how many) which salesman would give me back when he/she has to give me like 456 back. moneyBack 0 ==> [] moneyBack 10 ==> [(10,1)] moneyBack 123 ==> [(100,1),(10,2),(2,1),(1,1)] moneyBack 5326 ==> [(500,10),(100,3),(25,1),(1,1)] If anybody could point me in a right direction that would be great. Haskell seems very cool because the code is usually really short, but i just need a start. I need more examples than i can find from google (maybe i'm not using the right keywords). Thanks. -- View this message in context: http://www.nabble.com/School-assignment-help-tf4685176.html#a13388655 Sent from the Haskell - Hugs-Users mailing list archive at Nabble.com.
Hi
This is the place for questions specifically about the Hugs system -
for general Haskell help you will get a much larger audience on
haskell-cafe -AT- haskell.org - I suggest reposting this email to
there.
There is a page about how to ask for homework help on the Haskell
wiki: http://haskell.org/haskellwiki/Homework_help
Thanks
Neil
On 10/24/07, Urmastaag
Hello!
Can anybody point me to a right way here? I have those exercises in haskell that i cannot do, because haskell is so much different from other languages that i use. I have read so much from different manuals but i do not understand haskell enough yet.
First exercise:
I must find a shorter list. Here's how i did that, but my teacher said that it is unefficient way to do it.
getShorter :: [a] -> [a] -> [a] getShorter xs ys | length xs <= length ys = xs | otherwise = ys
How do i do it effective, so that i only check as many elements from lists as many are in the shortest list?
Second exercise:
Second exercise also need an effective answer:
I have to remove any occurances of certain number from list and give the number of how many times that number was removed.
Unefficient version: remCount :: Int -> [Int] -> (Int,[Int]) remCount n xs = (length xs - length ys, ys) where ys = [ x | x <- xs, x /= n]
Exercise three:
moneyBack :: Int -> [(Int,Int)]
I must print out all pairs of bank notes and (bank notes, how many) which salesman would give me back when he/she has to give me like 456 back.
moneyBack 0 ==> [] moneyBack 10 ==> [(10,1)] moneyBack 123 ==> [(100,1),(10,2),(2,1),(1,1)] moneyBack 5326 ==> [(500,10),(100,3),(25,1),(1,1)]
If anybody could point me in a right direction that would be great. Haskell seems very cool because the code is usually really short, but i just need a start. I need more examples than i can find from google (maybe i'm not using the right keywords).
Thanks.
-- View this message in context: http://www.nabble.com/School-assignment-help-tf4685176.html#a13388655 Sent from the Haskell - Hugs-Users mailing list archive at Nabble.com.
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Urmastaag