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// simple binary tree
template <class T> class BinaryTree 
{
    template <class U>  struct Node 
    {
        Item<U> item; // holds data
        Node<U> *left, *right; // references to childs
        Node<U> *p; // reference to parent
    };
    Node<T> *root;
public:
    BinaryTree(); // default constructor
    Node<T>* newNode(Node<T> *father, const Item<T>&); // creates new node with data
    int BinaryTree<T>::depth(Node<T> *node); // Compute the depth of a node
    .....
    .....
};

#include "BinaryTree.h"
 
// receives tree, father node, key. creates new Node with data and return it
template <class T> 
typename BinaryTree<T>::Node<T>* BinaryTree<T>::newNode(Node<T> *father, const Item<T> &other)
{
    BinaryTree<T>::Node<T> *node = (BinaryTree<T>::Node<T>*)malloc(sizeof(BinaryTree<T>::Node<T>));
    ..................
}
 
// Compute the depth of a node
template <class T>
int BinaryTree<T>::depth(Node<T> *node) 
{
    ..................
}
 
 
// initialized only for oppurtunity of separation declaration & initiation of template class in multiple files
template Item<char>;
template BinaryTree<char>;

// receives string in infix mode and reproduce the tree using postfix & infix data
template <class Q> BinaryTree<Q> RestoreTree(char*);
template <class T> void RestoreSubTree(char*, char*, BinaryTree<T>::Node<T>*, int);
 
void main()
{
    BinaryTree<char>::Node<char> n('c');  // ОШИБКА
}
 
// receives string in infix mode and reproduce the tree using postfix & infix data
template <class Q> 
BinaryTree<Q> RestoreTree(char *infix)
{
    char *postfix = ConvertToPostfix(infix);
 
    BinaryTree<char> tree;
    // reproduce the tree by recursive function
    RestoreSubTree(infix, postfix, tree.root, strlen(infix));
 
    return tree;
}
 
// НЕТУ ДОСТУПА К NODE
template <class T>
void RestoreSubTree(char *infix, char *postfix, BinaryTree<T>::Node<T> *node, int len)
{
    .......
}