restart:
with(Maplets[Elements]);
with(combinat, randcomb);

#  
problem6 := proc()
local respond,   U, finished, A, B, answer, m, CurrentMaplet;
   respond := (m,n) -> if (m=n) then RETURN(CORRECT) else RETURN(INCORRECT) fi; 
randomize();
U:={0,1,2,3,4,5,6};
  finished := false;
  while (not finished) do
     A:= randcomb(U,5);
      
      answer:=U minus A;

      m := Maplet( Window( 'title'="Complement", [[[cat("Let the universal set be ", convert(U,string), " and let set A be ",convert(A,string),".")],  "What is the A'?",TextField['TF1'](20)], 
        TextBox['TB1']('editable' = 'false'),
        [Button("Check", Evaluate('TB1'='respond(TF1, answer)')),
         Button("Quit", Shutdown("0")),
         Button("Another", Shutdown("1"))]
        ] ) ):

       CurrentMaplet := Maplets[Display](m);
       if (CurrentMaplet = "1") then finished := false else finished := true fi;
    end do;
end proc;

problem6();