Okinawa - Beijing - shanghai - hong kong - okinawa

Hello!

Is there anyway to fly from okinawa - beijing - shanghai - hong kong - okinawa without a visa? does the 72 hours start over why you fly from one part of china to another?

If not, can we do this.

okinawa - beijing - hongkong - shanghai - okinawa?

are you allowed to fly into China twice if your ticket is from another country?

Thank you for all the help!!!!