$ perl -le '
> %h = ( one => 1, two => 1, three => 1 );
> $inv = do{ local $" = q{|}; qr{^@{ [ qw{ two three } ] }$} };
> map $h{ $_ } = 0, grep ! /$inv/, keys %h;
> print qq{$_ - $h{ $_ }} for keys %h;'
three - 1
one - 0
two - 1
$