My pleasure - I think officially your problem would be the Socialist millionaires problem, but that is mostly only known as a derived form of yao's millionaire

My pleasure - I think officially your problem would be the Socialist millionaires problem, but that is mostly only known as a derived form of yao's millionaires problem, which has a much stronger cachet. https://en.wikipedia.org/wiki/Socialist_millionaire_problem https://en.wikipedia.org/wiki/Socialist_millionaire_problem