begin 
 real 
  a;
 begin 
  real 
   a;
  begin 
   real 
    a;
   begin 
    real 
     a;
    begin 
     real 
      a;
     begin 
      real 
       a;
      begin 
       real 
        a;
       begin 
        real 
         a;
        begin 
         real 
          a;
         begin 
          real 
           a;
          begin 
           real 
            a;
           begin 
            real 
             a;
            begin 
             real 
              a;
             begin 
              real 
               a;
              begin 
               real 
                a;

              end 
             end 
            end 
           end 
          end 
         end 
        end 
       end 
      end 
     end 
    end 
   end 
  end 

 end 

end