R for right, L for left, U for up, D for down, DL for down angled left, DR for down angled right. This is assuming you are facing right. Make sure to use a comma after every letter. Example: R, DR, D (Not a real command input).
As someone who doesn’t play Ryu or Terry... oy vey. I did so bad at this quiz. As a side note I think this type of quiz works better with the hints and answers reversed, since typing the names of these moves is a bit less awkward then having to type the inputs.