5.2 Data Types |

We need to define data types for AVL trees like we did for BSTs. AVL tree nodes contain all the fields that a BST node does, plus a field recording its balance factor:

144. <AVL node structure 144> = /* An AVL tree node. */structavl_node

{structavl_node*avl_link[2]; /* Subtrees. */void*avl_data; /* Pointer to data. */signedcharavl_balance; /* Balance factor. */ };

This code is included in 142.

We're using *avl_* as the prefix for all AVL-related identifiers.

The other data structures for AVL trees are the same as for BSTs.