Pascal :

var
n,y:integer;
begin
readln(n,y);
  case y of
  1,3,5,7,8,10,12:write('31');
  4,6,9,11:write('30');
  end;
  if y=2 then
  if (n mod 4=0) and (n mod 100<>0) or (n mod 400=0) then write('29') else write('28');
end.