diagnose 16_800F

begin
   integer g = 0

   routine p
      integer a = 10

      routine q
         integer b = 20

         routine r
            g = 1
            a = 11
            b = 21
         end

         r
         write(b,0);  newline
      end

      q
      write(a,0);  newline
   end

   p
   write(g,0);  newline
endofprogram