#The code not working

my ($common_ref, $total_ref) = calc_enthalpy (\%hash, \%enthalpy_hash);

@total = @$total_ref;
@common = @$common_ref;

print "TEST: @total  @common<P>";


  sub calc_enthalpy   {

                      my ($hash, $enthalpy_hash) = @_;
                      my (@common, @total);

                             foreach (keys %enthalpy_hash)      {


                                      if (exists $hash{$_})    {
                                              push @common, "$_ = ", $enthalpy_hash{$_} * $hash{$_}, "\n";
                                              push @total, $enthalpy_hash{$_} * $hash{$_}, "\n";
                                       }

                                    return (\@common, \@total);

                             }

   }


##</code><code>##


foreach (keys %enthalpy_hash)      {


        if (exists $hash{$_})    {
                push @common, "$_ = ", $enthalpy_hash{$_} * $hash{$_}, "\n";
                push @total, $enthalpy_hash{$_} * $hash{$_}, "\n";
        }
#  etc 

}