Write a function in HASKELL to reverse a string (or list) without using the built-in reverse...

Question

Question

Write a function in HASKELL to reverse a string (or list) without using the built-in reverse function.

Example:

Hello as olleh or [1,3,4,5] as [5,4,3,1].

Answer 1

Answer #1

reverseData :: [b] -> [b] --function declaration
--function definition

-- ++ is concatenation operator
reverseData [] = []
reverseData (a:input) = reverseData input ++ [a]

main = do
print(reverseData "hello") --calling a function
print(reverseData [1,3,4,5])

Output

"olleh"
[5,4,3,1]

Answer 2

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