@arr = map {qr/\Q$_\E/} @arr;
my @keepers = do {
    local $" = '|';
    grep { m/@arr/ } <>;
};

##</code><code>##

my (%hsh, @keepers);
@hsh{@arr} = ();
while (<>) {
    push @keepers, $_ if grep {exists $hsh{$_}} split;
}