1 for (int c0 = 1; c0 <= M; c0 += 1) { 2 S1(c0, 1); 3 for (int c1 = 2; c1 <= c0; c1 += 1) { 4 S1(c0, c1); 5 S2(c0, c1); 6 } 7 for (int c1 = c0 + 1; c1 <= M; c1 += 1) 8 S1(c0, c1); 9 } 10