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# System prepended metadata

title: Hello?!

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# Hello?!


> You're given a list of integers from 0 to n, permuted and with one or 
> more numbers removed. Write an  algorithm to identify the missing numbers.

First step:
- sort asceding (or descending) the provided data
- value at position 1 must be equal to value at position 0 + 1

sortMyList :: [Int] -> [Int]
sortMyList = sort

checkValue :: Int -> Int -> Maybe Int
checkValue valueToCheck nextValue = 
    if valueToCheck + 1 == nextValue
        then Nothing
        else Just valueToCheck
        
        
solveProblem :: [Int] -> [Int]
solveProblem list = 
        
[1, 2, 3] ==> should return [Nothing, Nothing, Nothing]


We want:


solveProblem [1, 2, 3] = [Just 0, Nothing, Nothing]
solveProblem [10, 5, 9] = ... ?
solveProblem [0,1,2,3] = []




