8.1 Data Types [ToC] [Index]     [Skip Fwd]     [Prev] [Up] [Next]

The TAVL node structure takes the basic fields for a BST and adds a balance factor for AVL balancing and a pair of tag fields to allow for threading.

299. <TAVL node structure 299> =
/* Characterizes a link as a child pointer or a thread. */
enum tavl_tag 
  { TAVL_CHILD, /* Child pointer. */ TAVL_THREAD /* Thread. */ }; /* An TAVL tree node. */ struct tavl_node
  { struct tavl_node *tavl_link[2]; /* Subtrees. */ void *tavl_data; /* Pointer to data. */ unsigned char tavl_tag[2]; /* Tag fields. */ signed char tavl_balance; /* Balance factor. */ };

This code is included in 297.


1. struct avl_node contains three pointer members and a single character member, whereas struct tavl_node additionally contains an array of two characters. Is struct tavl_node necessarily larger than struct avl_node? [answer]