Haskell program will not end if input = 0

Question

When the user inputs number m = 0, the program will never stop counting. Is there any way how to take care of that? so if the user inputs 0 the program will end.

import Control.Monad (replicateM)

transpose :: [[a]]->[[a]]
transpose ([]:_) = []
transpose x = (map head x) : transpose (map tail x)
.
.
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Answer 1

You missed a case in transpose that is triggered by entering 0:

transpose :: [[a]]->[[a]]
transpose [] = []
transpose ([]:_) = []
transpose x = (map head x) : transpose (map tail x)

And the above is quite dangerous, as 'head' and 'tail' might fail:

transpose [[0],[]]

[[0,* Exception: Prelude.head: empty list