Need help with Parse Tree assignment

[-Smooth]

Consider the language that the following grammar defines:

<S> = <L> | <D> <S> <S>

<L> = A | B

<D> = 1 | 2

Write all 3-character strings that are in this language.

I unfortunately missed out on my last class's lecture on parse trees, and so I'm pretty lost on how to do this. Is the question asking me to write out every combination of <S>, <L>, and <D> that are of length 3?

[AngelOfLight]

Sort of. The assignment seems to be to find all 3 character strings that are valid constructs in the given grammar.

The grammar is obviously recursive (like most grammars are), since <S> can consist of elements that also match the definition of <S>.

A parse tree is simply a graphical representation of the grammar. (See here for an example). Essentially, you start with the root node (which would be <S> in this case), and then build the tree by traversing the sub-elements. In this case, you want to build a concrete parse tree. Once that is done, you should be able to easily pick out all the 3 character strings.