1{
2  for (int c0 = 0; c0 <= 8; c0 += 1) {
3    for (int c1 = 0; c1 <= -c0 + 8; c1 += 1)
4      for (int c2 = 10 * c0; c2 <= 10 * c0 + 9; c2 += 1)
5        for (int c3 = 10 * c1; c3 <= 10 * c1 + 9; c3 += 1)
6          A(c2, c3);
7    for (int c1 = -c0 + 9; c1 <= -c0 + 10; c1 += 1)
8      for (int c2 = 10 * c0; c2 <= min(10 * c0 + 9, -10 * c1 + 100); c2 += 1)
9        for (int c3 = 10 * c1; c3 <= min(10 * c1 + 9, -c2 + 100); c3 += 1)
10          A(c2, c3);
11  }
12  for (int c0 = 9; c0 <= 10; c0 += 1)
13    for (int c1 = 0; c1 <= -c0 + 10; c1 += 1)
14      for (int c2 = 10 * c0; c2 <= min(10 * c0 + 9, -10 * c1 + 100); c2 += 1)
15        for (int c3 = 10 * c1; c3 <= min(-c2 + 100, 10 * c1 + 9); c3 += 1)
16          A(c2, c3);
17}
18