How do you solve this Haskell problem using a fold map and take?
- by Linda Cohen
Define a function replicate which given a list of numbers returns a
list with each number duplicated its value. Use a fold, map, and take
.. replicate [5,1,3,2,8,1,2]
output: [5,5,5,5,5,1,3,3,3,2,2,8,8,8,8,8,8,8,8,1,2,2]
I've figure this out using List comprehension and recursion:
replicate2 [] = []
replicate2 (n:nn) = take n(repeat n) ++ replicate2 nn
but how would you use fold and map to do this?
so far I have: replicate n = map (foldl1 (take n(repeat n)) n) n
which is obviously wrong, but I think I am close..
so any help would be nice, THANKS!
