my %net = ( ... ); my $start = '1.2.3.4'; my $end = '1.2.3.6'; print find_pathr( \%net, $end, $start ) . "\n"; sub find_pathr { my ( $net, $end, @list ) = @_; my $curr; do { $curr = shift @list; } until ( ! @list or exists $$net{ $curr } ); return "No path!" unless exists $$net{$curr}; return $end if $curr eq $end; unshift @list, @{ delete $$net{ $curr } }; return "$curr->" . find_pathr( $net, $end, @list ); }