1 for (int c1 = 1; c1 <= M; c1 += 1) 2 S1(0, c1); 3 for (int c0 = 1; c0 <= N; c0 += 1) 4 for (int c1 = 1; c1 <= M; c1 += 1) 5 S2(c0, c1); 6