1 for (int c0 = 1; c0 < O; c0 += 1) {
2   for (int c1 = Q; c1 < N; c1 += 1) {
3     for (int c2 = P; c2 < M; c2 += 1)
4       S1(c0, c1, c2);
5     for (int c2 = 1; c2 < M; c2 += 1)
6       S2(c0, c1, c2);
7   }
8   for (int c1 = 1; c1 < N; c1 += 1) {
9     for (int c2 = P; c2 < M; c2 += 1)
10       S3(c0, c1, c2);
11     for (int c2 = 1; c2 < M; c2 += 1)
12       S4(c0, c1, c2);
13   }
14 }
15