I know it's 1, but my dad keeps on saying it's zero. He thinks it's like that cycology thing when they say 1+1=3, because 1 of them split into 2. But I don't think it's like that at all.
I don't know how to explain it but my pre-algebra teacher said it was 1 and a whole bunch of other people but he still thinks it's 0, So if you do know how to explain it, please do.