@list = grep { $_ != 2 && $_ != 4 } @list;

##</code><code>##

my @foo = 1..10;

for (my $i = 0; $i < @foo; $i++)
{
        print "$i ($foo[$i])\n";
        if ($foo[$i] == 5 || $foo[$i] == 6)
        {
                splice(@foo, $i, 1);
                redo;
        }
}