for (int c0 = 1; c0 <= 36; c0 += 1) {
if (c0 <= 3) {
for (int c1 = 1; c1 <= 9; c1 += 1)
s1(c1, c0);
} else if (c0 <= 9) {
for (int c1 = 1; c1 <= 9; c1 += 1) {
if (c0 % 4 == 0)
s0(c1, c0 / 4);
s1(c1, c0);
}
} else if (c0 % 4 == 0) {
for (int c1 = 1; c1 <= 9; c1 += 1)
s0(c1, c0 / 4);
}
}