Question

So I’m trying to learn python on my own, and am doing coding puzzles. I came across one that pretty much ask for the best position to stand in line to win a contest. The person running the contest gets rid of people standing in odd number positions.

So for example if 1, 2, 3, 4, 5

It would get rid of the odd positions leaving 2, 4

Would get rid of the remaining odd positions leaving 4 as the winner.

When I’m debugging the code seems to be working, but it’s returning [1,2,3,4,5] instead of the expected [4]

Here is my code:

def findWinner(contestants):
    if (len(contestants) != 1):
        remainingContestants = []
        for i, contestant in enumerate(contestants, 1):
            if (isEven(i)):
                remainingContestants.append(contestant)
        findWinner(remainingContestants)
    return contestants

Am I not seeing a logic error or is there something else that I’m not seeing?

Answer 1

You must return the value from the recurse function to the caller function:

return findWinner(remainingContestants)

else you would return just the original value without any changes.

def findWinner(contestants):
    if (len(contestants) != 1):
        remainingContestants = []
        for i, contestant in enumerate(contestants, 1):
            if (isEven(i)):
                remainingContestants.append(contestant)
        return findWinner(remainingContestants) # here the value must be return
    return contestants # without the return above, it will just return this value(original)