Add one to the last element of a list

Hello and welcome to another one day one answer series. In this article, we will create a python method which will do the following actions.

  1. Takes in a list of numbers.
  2. If the number is less than 0 or it is a double digits number then returns None.
  3. If it is an empty list then returns None.
  4. Else joins the numbers in the list together to create a larger number, for example, if a list consists of [1, 2, 3] then the larger number will become 123. Next, add one to that new number, so 123 becomes 124.
  5. Finally turns that new number back to a list, so 124 becomes [1, 2, 4] and returns that new list.

Below is the solution for this question.

def up_array(arr):

    str_ = ''
    if(len(arr) == 0):
        return None
    for num in arr:
        if(num < 0 or num > 9):
            return None
            str_ += str(num)
    total = str(int(str_) + 1)
    arr = []

    for number in total:

    return arr

That is it, hope you like this article.


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I was trying to share a more pythonic solution but it seems there is no way to keep code formatting in comments… Tough