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When I posted this puzzle, I made a stupid mistake resulting from not double checking my thinking. I did not notice this until one user posted an incomplete answer, which was only missing an answer for the part I had goofed up. I upvoted him, and said I would fix the puzzle later, at which point he could solve the revised puzzle, and I could accept. I was busy, and was only able to fix the puzzle very recently. It was immediately answered (fully correctly) by someone else. So now I have the conundrum, what do I do? Do I wait for the original solver to post his revised answer (because it's my fault that he had to revise it), or do I accept the complete answer that the new solver posted?