%HoA =(
##id =>["term","parent_id","left_id", "right_id"]
1 => ["Body Regions","","",""],
2 => ["Extremities","1","",""],
3 => ["Arm","2","",""],
4 => ["Elbow","2","",""],
5 => ["Hand","2","",""],
6 => ["Fingers","5","",""],
7 => ["Thumbs","6","",""]
);

##</code><code>##

my %HoA;
my $k;
my $root = 1;
my $ctr =1;

for $k (sort keys %HoA){
walktree($root) unless $k eq"";

}

sub walktree{
my $id = shift;
$HoA{$k}[2]=$ctr++ if $id = $k;

##The walktree recursive sub below enters an eternal loop 
##and doesn't execute properly.  When I tried to push the 
##children elements to a temporary array, it worked just 
##fine.  Would it be the $id???
walktree($id) if $id =$HoA{$k}[1] ;

$HoA{$k}[3]=$ctr++;
local $" = "|";
print "$k = @{$HoA{$k}}\n";
}