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{
    TREE *node=NULL;

    /*
     *		Search for the symbol in the subtree of the tree node.
     */
    node=find_symbol_add(tree, symbol);

    /*
     *		Increment the symbol counts
     */
    if((node->count<65535)) {
	node->count+=1;
	tree->usage+=1;
    }

    return(node);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Find_Symbol
 *
 *		Purpose:		Return a pointer to the child node, if one exists, which
 *						contains the specified symbol.
 */
TREE *find_symbol(TREE *node, int symbol)
{
    register int i;
    TREE *found=NULL;
    bool found_symbol=FALSE;

    /*
     *		Perform a binary search for the symbol.
     */
    i=search_node(node, symbol, &found_symbol);
    if(found_symbol==TRUE) found=node->tree[i];

    return(found);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Find_Symbol_Add
 *
 *		Purpose:		This function is conceptually similar to find_symbol,
 *						apart from the fact that if the symbol is not found,
 *						a new node is automatically allocated and added to the
 *						tree.
 */
TREE *find_symbol_add(TREE *node, int symbol)
{
    register int i;
    TREE *found=NULL;
    bool found_symbol=FALSE;

    /*
     *		Perform a binary search for the symbol.  If the symbol isn't found,
     *		attach a new sub-node to the tree node so that it remains sorted.
     */
    i=search_node(node, symbol, &found_symbol);
    if(found_symbol==TRUE) {
	found=node->tree[i];
    } else {
	found=new_node();
	found->symbol=symbol;
	add_node(node, found, i);
    }

    return(found);
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Add_Node
 *
 *		Purpose:		Attach a new child node to the sub-tree of the tree
 *						specified.
 */
void add_node(TREE *tree, TREE *node, int position)
{
    register int i;

    /*
     *		Allocate room for one more child node, which may mean allocating
     *		the sub-tree from scratch.
     */
    if(tree->tree==NULL) {
	tree->tree=(TREE **)malloc(sizeof(TREE *)*(tree->branch+1));
    } else {
	tree->tree=(TREE **)realloc((TREE **)(tree->tree),sizeof(TREE *)*
				    (tree->branch+1));
    }
    if(tree->tree==NULL) {
	error("add_node", "Unable to reallocate subtree.");
	return;
    }

    /*
     *		Shuffle the nodes down so that we can insert the new node at the
     *		subtree index given by position.
     */
    for(i=tree->branch; i>position; --i)
	tree->tree[i]=tree->tree[i-1];

    /*
     *		Add the new node to the sub-tree.
     */
    tree->tree[position]=node;
    tree->branch+=1;
}

/*---------------------------------------------------------------------------*/

/*
 *		Function:	Search_Node
 *
 *		Purpose:		Perform a binary search for the specified symbol on the