var startyear, endyear, year, longyear, ayear, weekday;

procedure calcweekday;
begin
  weekday := ayear + ayear / 4 - ayear / 100 + ayear / 400;
  weekday := weekday - (weekday / 7) * 7
end;

procedure calclongyear;
begin
  longyear := 0; ayear := year;
  call calcweekday;
  if weekday = 4 then longyear := 1;
  ayear := year - 1;
  call calcweekday;
  if weekday = 3 then longyear := 1
end;

begin
  ? startyear;
  ? endyear;
  year := startyear;
  while year <= endyear do
  begin
    call calclongyear;
    if longyear <> 0 then ! year;
    year := year + 1
  end
end.