for (int c0 = 1; c0 <= 18; c0 += 1) {
if (c0 >= 2 && c0 <= 9) {
for (int c1 = 1; c1 <= 9; c1 += 1) {
if (c0 % 2 == 0)
s0(c1, c0 / 2);
s1(c1, c0);
}
} else if (c0 == 1) {
for (int c1 = 1; c1 <= 9; c1 += 1)
s1(c1, 1);
} else if (c0 % 2 == 0) {
for (int c1 = 1; c1 <= 9; c1 += 1)
s0(c1, c0 / 2);
}
}