Introduction - If you have any usage issues, please Google them yourself
(1) Insert a new node (2) pre-order, in sequence, after the tree traversal (recursive) (3) pre-order, in sequence, after traversing a non-recursive algorithm (4) hierarchical tree traversal (5) in binary Find a given keyword (function returns a value of 1 on success, failure 0) (6) exchange about each node subtree (7) the depth of the binary tree (8) leaf nodes (9) delete a node