What is the funniest joke you have heard so far?

I met a psycho shop! When I was shopping, I heard that "you can't buy two dollars at a loss, but you can't be fooled by two dollars." I was silently brainstorming the lines behind, and then I heard the speaker continue to say, "You can't buy anything for two dollars, and the audience sells five dollars! Sell five pieces in the audience! " Shit, the most basic trust between people is gone!