ok, i add some nodes (the addnode routine works, i know), and then call display: 
$q = new Tree;
$q->addnode(4);
$q->addnode(3);
$q->addnode(5);
$q->addnode(14);
$q->addnode(15);
$q->addnode(7);
$q->addnode(19);
$q->display;

[download]
so the tree should look like this: 
  4
 / \
3   5
     \
     14
     /\
    7  15
        \
        19

[download]
So i'd expect the display routine to list the numbers in order, starting with the lowest. In fact, what I get is: 
3
3

[download]
What seems to be happening is that it correctly finds it's starting point, at which point there are 2 levels of recursion. It prints the node value, then goes back to the calling level, but still refers to the lowest level node. So print $head->{Val}, "\n"; still, for some reason prints '3'. Incidentally, if i run it from right to left, i get 
19
19
19
19
19

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Do you see what i mean? When a subroutine ends and passes control back up to the calling level, is $head not being returned to it's value in the calling routine?

In reply to Re: recursion by Basilides
in thread Trouble traversing binary tree (was: recursion) by Basilides

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