var
  i, j: integer;
  m, n, k: real;

begin
  readln(m, n);
  m := m * 30;
  n := n * 6;
  k := 0;
  while (m - n <> 90) or (m - n  <> 270) or (m - n <> -90) or (m - n  <> -270) do
  begin
    m := m + 1;
    n := n + 12;

    if n = 360 then begin
      n := 0;
      m := m + 30;
    end;
    if m = 360 then begin
      m := 0;
      k := k + 60;
    end;
    k := k + 1;
  end;
  write(k);


end.