Traveling to Shanghai, leaving for Hong Kong for a few days, returning back to Shanghai

Hello,
So my friend and I have planned to travel from LAX to Shanghai. We will be in Shanghai for our first few days but then have planned (already booked everything) to go to Hong Kong for a couple of days. Since our return flight leaves from Shanghai, we will return to Shanghai a day before our return flight to LAX. From this, I know we will need to apply for multiple entry because Hong Kong isn't part of mainland China. My concern now is, the only thing we don't have booked yet is a hotel for that last night in Shanghai... How will that affect our chances of getting the Visa since we are planning to leave and return to mainland China and not having ALL our nights on mainland booked? We have confirmation of our roundtrip from LA-Shanghai-LA as well as our roundtrip from Shanghai-HK-Shanghai. We also have confirmation of our hotel stay in Shanghai and hotel stay in HK.