#! perl -slw
use strict;
$|=1;

my $tree = {
    top => {
        inetUser => {},
        person => {
	        organizationalPerson => {
	            managedPerson => {
	                personnel => {}, 
	            }, 
	        }, 
	     },
        application => {
            managedApplication => {}, 
        }, 
    },
 };
 
sub explore;
sub explore {
	my( $tree, $leaf ) = @_;
	for my $node ( keys %$tree ){
		return $node if $node eq $leaf;
		next unless keys %{ $tree->{ $node } };
		my @found = explore $tree->{ $node }, $leaf;
		return ( $node, @found ) if @found;
	}
	return;
}

printf "Looking for %-20s: %s\n", $_, join ' -> ', explore $tree, $_ 
	for qw[ fred inetUser managedApplication personnel ];
	
__END__
P:\test>test
Looking for fred                :
Looking for inetUser            : top -> inetUser
Looking for managedApplication  : top -> application -> managedApplication
Looking for personnel           : 
    top -> person -> organizationalPerson -> managedPerson -> personnel