perl -MData::Dumper=Dumper -le '%hash = ( a=>3, b=>4, c=>1, d => 7 ); @ary = qw(b c); @nhash{@ary} = delete @hash{@ary}; print Dumper \%hash; print Dumper \%nhash;'

$VAR1 = {
          'a' => 3,
          'd' => 7
        };

$VAR1 = {
          'c' => 1,
          'b' => 4
        };