its tough superhero and twice tough resist supervillain cool math suppose you re ordinary Batman ordinary city Gotham your enemy Joker mine build city administration minute neutralize charge to enter cancel code bomb control panelHowever mad man decide hint this morning mayor find playing card pillow there line write cardthe bomb note say JxA a positive integer you suspect cancel code integer x meet equation JxA now order decide neutralize bomb run life you ve get count distinct positive integer x meet equation