@this = @last;
        @last = ();

##</code><code>##

        @last = @this;
        @this = ();

##</code><code>##

my @match = ( $$a1[$b1] );

##</code><code>##

@{$a1}[ ($b1-$longest+1), $b1 ]

##</code><code>##

@{$a1}[ ($b1-$longest+1) .. $b1 ]