/*******************************************************************************++  LEDA 3.5+++  avl_tree.h+++  Copyright (c) 1995, 1996, 1997  by  LEDA Software GmbH+  Postfach 151101, 66041 Saarbruecken, Germany+  All rights reserved.+ *******************************************************************************/#ifndef LEDA_AVL_TREE1_H#define LEDA_AVL_TREE1_H//------------------------------------------------------------------------------//// avl_tree:////           AVL trees (derived from bin_tree)//// Stefan N"aher (1993)////------------------------------------------------------------------------------#include <LEDA/basic.h>#include <LEDA/impl/bin_tree.h> typedef bin_tree_node* avl_tree_item; class __exportC avl_tree : public bin_tree{   // balance of node v with right (left) subtree R (L)  // bal(v) =  height(R) - height(L) in [-1 ... +1]  //  // all created nodes have balance 0  int root_balance() { return 0; }  int leaf_balance() { return 0; }  int node_balance() { return 0; }  void insert_rebal(avl_tree_item);  void del_rebal(avl_tree_item, avl_tree_item);public:  avl_tree() {} ~avl_tree() {}  avl_tree(const avl_tree& T) : bin_tree(T) {}  avl_tree& operator=(const avl_tree& T)   { bin_tree::operator=(T); return *this; }};#endif