{

  for (int c0 = a; c0 <= min(a + 9, b); c0 += 1)

    s0(c0);

  for (int c0 = a + 10; c0 <= min(a + 19, b); c0 += 1) {

    s0(c0);

    s1(c0);

  }

  for (int c0 = max(a + 10, b + 1); c0 <= min(a + 19, b + 10); c0 += 1)

    s1(c0);

  for (int c0 = a + 20; c0 <= b; c0 += 1) {

    s0(c0);

    s1(c0);

    s2(c0);

  }

  for (int c0 = max(a + 20, b + 1); c0 <= b + 10; c0 += 1) {

    s1(c0);

    s2(c0);

  }

  for (int c0 = max(a + 20, b + 11); c0 <= b + 20; c0 += 1)

    s2(c0);

}