my %find;
@find{ qw( this that other ) } = ();
my $found = grep { exists $find{$_} && ( delete $find{$_} || 1 ); } @big_list;
print "Success!\n" if $found == 3;

##</code><code>##

my %big_set;
@big_set{ @big_array } = ();
my @find = qw( this that other );
my $found = grep{ exists $big_set{$_} } @find;
print "Success!\n" if $found == 3;