AoC 2022, day 4

my ($cnt-p1, $cnt-p2) = 0, 0;

for $*IN.lines.map({ .comb(/\d+/)».Int }) -> (\a0, \a1, \b0, \b1) {
    my @A = a0..a1;
    my @B = b0..b1;
    my \union-size = @A (|) @B;

    ++$cnt-p1 if union-size == +@A | +@B;
    ++$cnt-p2 if union-size <  +@A + +@B;
}

put 'part 1: ', $cnt-p1;
put 'part 2: ', $cnt-p2;