1 for (int c0 = 1; c0 <= M; c0 += 1) 2 S1(c0); 3 for (int c0 = 1; c0 <= M; c0 += 1) 4 for (int c1 = 2; c1 <= N; c1 += 1) 5 S2(c0, c1); 6 for (int c0 = 1; c0 <= M; c0 += 1) 7 for (int c1 = 1; c1 < N; c1 += 1) 8 S3(c0, c1); 9