Single or Double Entry required ?

We are flying from Melbourne to Beijing early October, 8 day touring on to Shanghai then on 5 day/night cruise to Fukuoka, Japan - Busan, South Korea and back to China (Tianjin). Docking at 7am then transfer to airport for flight out that day at 3.10pm.
Can anyone tell me if we require a single or double entry, we have been getting conflicting advice?
Cheers