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Python

Derek Derek
Derek Derek
8,744 Points
Posted by Derek Derek
Derek Derek
8,744 Points

[python] Find all subsets

My understanding of recursion is very weak. So, while I was practicing simple recursion questions, I got stuck on this question. I tried inserting print statements but I'm still not sure. Can you please describe how return [prev] contains every subset in the end? Thank you for your help.

def find_subsets(prev, subset):
    if subset:
        cur = subset[0]
        # print "cur", cur

        return find_subsets(prev, subset[1:]) + \
                find_subsets(prev + [cur], subset[1:])
    # print "prev", [prev]
    return [prev]

# print find_subsets([],[1])
print find_subsets([],[2, 1, 3])