Problem 3
(*) Find the K’th element of a list. The first element in the list is number 1.
Example:
* (element-at '(a b c d e) 3) c
Example in Haskell:
Prelude> elementAt [1,2,3] 2 2 Prelude> elementAt "haskell" 5 'e'
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| — problem 3 | |
| — find elementat indexed location | |
| elementat :: [a] -> Integer -> Maybe a | |
| elementat [] _ = Nothing | |
| elementat [x] 1 = Just x | |
| elementat [x] _ = Nothing | |
| elementat xs 1 = Just (head xs) | |
| elementat (_:xs) n = elementat xs (n – 1) | |