For the grammar above , show the list of tokens after scanning, the list of tokens after screening, the parse tree, and the steps taken to constrain and generate code, for the following sample input program:

program Two (file);

var a integer;

begin { comment }

a = 7;

if a

writeln(a);

end.

->Heading Deln Block '.' -ar' Integer ';' -'program' Files'' 1.Program => 'program ' cln 3. Heading -> 'heading' => ' files' Files -'begin' (Statement 'end' 'block' -'writelIn 6. Statement -> 'writeln'''Expression')' -> Expression -> 'if' Expression 'then ' statement => 'assign ", statement => "f' Expression -> Term 'Term 10 11. Term 12 13. 14. Integer -Term -> -> string> -integer" > ' integer