How can you use break with levels to exit nested loops and also execute code after the loops?

How can you use break with levels to exit nested loops and also execute code after the loops?

for ($a = 0; $a < 3; $a++) {
    for ($b = 0; $b < 3; $b++) {
        if ($b == 1) {
            break 2;
        }
        echo "$a$b ";
    }
}
echo "Done";