Tree traversal is naturally recursive and easily could be deep enough to hit the default limit.

package Node;
sub new {
    my ($class, $value) = @_;
    my $self = {
        value => $value,
        left  => undef,
        right => undef,
    };
    bless $self, $class;
    return $self;
}

# Recursive inorder traversal function
sub inorder_traversal {
    my ($node) = @_;
    return unless $node;  # Base case: return if node is undefined

    # Traverse the left subtree
    inorder_traversal($node->{left});

    # Visit the root node
    print $node->{value}, " ";

    # Traverse the right subtree
    inorder_traversal($node->{right});
}

# Example usage
package main;

# Create a sample binary tree
my $root = Node->new(1);
$root->{left} = Node->new(2);
$root->{right} = Node->new(3);
$root->{left}->{left} = Node->new(4);
$root->{left}->{right} = Node->new(5);

say "Inorder Traversal: ", inorder_traversal($root);
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