Public restrooms are notoriously bad in China, so the authorities there are cracking down with a new "two flies only" rule:
Authorities in the Chinese capital have set new standards for public toilets, including a stipulation that they should contain no more than two flies.
The new rules, published by the commission of city administration, also set standards on odour and cleaning litter bins.
The third fly will mercilessly hunted down and swatted: Link