Transit visa for Australian Passport Holder

I have an Australia Passport. I intend to fly to Shanghai from Melbourne on 24 February 2018 and depart Shanghai on a cruise ship (Majestic Princess) to Singapore on 25 February 2018. I will be returned on the same cruise ship to Shanghai on 25 March 2018 and return to Melbourne on 26 March 2018. Do I Need to apply for visa or can I apply for a transit visa on arrival at the airport and leave by the seaport? And on 25 March 2018, I apply for a transit visa from the seaport and fly out of Shanghai by air? Your help and reply will be greatly appreciated. Thank You.