c++ iteratively destroying a binary tree -

i trying write code iteratively destroys binary tree. know recursion easier, thought try iteratively (albeit using c notation , using structures, no need classes). thinking following:

void delete_tree (node *p_tree){ node *local_node; node *parent; int left_or_right; while (p_tree->p_left != null || p_tree->p_right != null){     parent = p_tree;     if (parent->p_left != null){         local_node = parent->p_left;         left_or_right = 1;     } else {         local_node = parent->p_right;         left_or_right = 2;     }     while (local_node->p_left != null || local_node->p_right != null){         if (local_node->p_left == null){             parent = local_node;             local_node = local_node->p_right;             left_or_right = 2;         } else if (local_node ->p_right == null){             parent = local_node;             local_node = local_node->p_left;             left_or_right = 1;         } else {             parent = local_node;             local_node = local_node->p_left;             left_or_right = 1;         }     }     cout << "deleting node value: " << local_node->key_value << endl;     delete local_node;     local_node = null;     if (left_or_right == 1){         parent->p_left = null;     } else if (left_or_right == 2){         parent->p_right = null;     } } cout << "deleting node value: " << p_tree->key_value << endl; delete p_tree; p_tree = null; 

}

i don't know wrong logic. goes this. traverse down binary tree until hit node no children, delete node. repeat until have original parent node. delete that.

edit: i've changed code in response suggestions. seems work , there no infinite loop, when try print out contents of binary tree, function gets stuck in infinite loop. know print function correct, there must still wrong delete_tree function.

one error here:

while (local_node->p_left != null && local_node->p_left != null) 

you're iterating downwards while node has 2 children. want check || instead of &&.