$direction = shift;
%iface = (
          "if${direction}Octets.2"   => 'FastEthernet0/1',
          "if${direction}Octets.3"   => 'FastEthernet0/2',
          "if${direction}Octets.4"   => 'FastEthernet0/3',
          "if${direction}Octets.5"   => 'FastEthernet0/4',
          "if${direction}Octets.26"  => 'GigabitEthernet0/1',
  );

foreach my $oid (sort keys(%iface)) {
  %oids = ("$iface{$oid}" => `$snmpwalk $ip $community $oid`);
}

##</code><code>##

foreach my $oid (sort keys(%iface)) {
  @oids = ({"$iface{$oid}" => `$snmpwalk $ip $community $oid`});
}