#! perl -slw
use strict;

# gen some test data (often generates warnings too)
#my @a = map{ int rand 100 } 1 .. 100; print "@a";
#my @b; push @b, @a[ ($_ = rand(100)) .. ($_ + rand(10)) ] for 1 .. 10; print "@b";

my @a = qw(fred bob joe jim mary elaine);
my @b = qw(frank joe jim mary bob);

my %b; @b{ @b } = ();
my $b = join ',', @b ;

my @subsets;
my $start = 0;

OUTER: {
	for( $start .. $#a ) {
		next if exists $b{ $a[$_] };
		if( $_ > $start+1 ) {
			my $a = join ',', @a[ $start .. ($_-1) ];
			push @subsets, [ ($_ - 1 - $start), $start, $_ -1 ] if 1+index( $b, $a );
		}
		$start++;
		redo OUTER;
	}
}

my $longest = [0];
$_->[0] > $longest->[0] and $longest = $_ for @subsets;


print "@a[ $longest->[1] .. $longest->[2] ]";