compute-sa.p6

sub round-up-to-multi($i, $m) {
    (($i + $m - 1) div $m) * $m
}

sub compute-sa(+@_) {
    my $size = 0;
    my $align = 0;

    for @_ -> ($s, $a) {
        $size = round-up-to-multi($size, $a) + $s;
        $align = $a if $a > $align;
    }

    $size = round-up-to-multi($size, $align);
    ($size, $align);
}

say compute-sa <4 4>, <3 1>, <2 2>;