How do I do the following in C language:

1. return an AST node representing the type of arrays of arrays of strings (that is, what wed write as string[][] in a source program).

2. The function get_inner_type should take an AST node, check whether it represents an array type, and if so, return its inner type. For instance, if you call get_inner_type on a type node representing int[], it should return a type node representing int. If called on a non-array type, it should return NULL.