All joking aside, what would you do if you met the president face to face?

I am appealing to everyone’s grown up side here.

I have seen the jokes and insults about President Trump.
I am asking now, if you met face to face with him, how would you behave? What would you say?
Here are some examples of how an unexpected meet might occur:
You are walking into Burger King, and some tall guy on his way out holds the door for you.

You win third place in a writing contest, and the prize is a trip to the White House.

You are in the hospital after rescuing two kids and a dog from a burning home. Our prez visits to honor your bravery.

These are only suggestions to help you answer the question.

Please be honest.
Judging from the way threads keep going here, I picture jellies behaving like monkeys if a face to face meeting occurred.
I am disappointed by that.