我正在创建一个自排序二进制搜索树的任务，每次尝试将重复元素插入树时都会重新组织它。我遇到了一些需要帮助解决的错误。
首先，树的根永远不会改变（我假设问题出在 RotateLeft 或 RotateRight 方法中）当第一个副本进入时，根永远不会更改为现在更高优先级的节点。
我得到的第二个错误是 BAD ACCESS ERROR（我已经注意到它在下面的代码中的位置），我猜它也是来自这些 Rotate 方法之一。
#ifndef SelfOrganizingTree_SOBTree_h
#define SelfOrganizingTree_SOBTree_h
#include "BinaryNode.h"
#include "bst.h"
template <class T>
class BinaryNode;
template <class T>
class SOBTree: public BinarySearchTree<T> {
public:
SOBTree();
void insert( const T& x );
void remove( const T& x );
bool isEmpty() const;
void printTree() const;
int reportComparisonCount();
double reportCPUTime();
private:
void insert( const T & x, BinaryNode<T> * & t , BinaryNode<T> * & rootNode);
void RotateRight(BinaryNode<T> * & root );
void RotateLeft(BinaryNode<T> * & root );
void printTree(BinaryNode<T> *t) const;
BinaryNode<T> *root;
void balance (BinaryNode<T> * & root);
};
template <class T >
SOBTree<T> :: SOBTree()
{
root = NULL;
}
/**
* Insert x into the tree
*/
template <class T >
void SOBTree<T > :: insert( const T & x )
{
insert( x, root , root);
}
/**
* Internal method to insert into a subtree.
* x is the item to insert.
* t is the node that roots the subtree.
* Set the new root of the subtree.
*/
template <class T>
void SOBTree<T> :: insert( const T & x, BinaryNode<T> * & t , BinaryNode<T> * & rootNode)
{
// BinaryNode<T> *current = t;
if( t == NULL ){
t = new BinaryNode<T>( x, NULL, NULL, rootNode );
//cout << t->element << endl;
t->priority++;
}
else if( x < t->element ){
//cout << "left" << endl;
insert( x, t->left , t);
}
else if( t->element < x ){
//cout << "right" << endl;
insert( x, t->right , t);
}
else{
//cout << "match found" << endl;
t->priority++; // Duplicate; rotate right or left if priority is higher than the root
balance(t);
}
}
template <class T>
void SOBTree<T>::balance (BinaryNode<T> * & rootN){
cout << "root: " << root->element << endl;
if (rootN->parent && rootN->priority > rootN->parent->priority) { //THIS IS WHERE THE BAD ACCESS ERROR IS BEING THROWN
if (rootN->parent->left == rootN) {
RotateLeft(rootN->parent);
balance(rootN->parent);
}else if (rootN->parent->right == rootN){
RotateRight(rootN->parent);
balance(rootN->parent);
}
}
}
template <class T>
void
SOBTree<T>::RotateLeft(BinaryNode<T> * & rootN) {
/*
Let P be Q's left child.
Set P to be the new root.
Set Q's left child to be P's right child.
Set P's right child to be Q.
*/
BinaryNode<T> * oldRoot = rootN;
// perform rotation
rootN = rootN->left;
oldRoot->left = rootN->right;
rootN->right= oldRoot;
}
template <class T>
void
SOBTree<T>::RotateRight(BinaryNode<T> * & rootN) {
/*
Let Q be P's right child.
Set Q to be the new root.
Set P's right child to be Q's left child.
Set Q's left child to be P.
*/
BinaryNode<T> * oldRoot = rootN;
// perform rotation
rootN = rootN->right;
oldRoot->right = rootN->left;
rootN->left = oldRoot;
}
template <class T>
bool SOBTree<T> :: isEmpty( ) const
{
return root == NULL;
}
/**
* Print the tree contents in sorted order.
*/
template <class T>
void SOBTree<T> :: printTree( ) const
{
if( isEmpty( ) )
cout << "Empty tree" << endl;
else
printTree( root );
}
template <class T>
void SOBTree<T> :: printTree( BinaryNode<T> *t ) const
{
if( t != NULL )
{
printTree( t->left );
cout << t->element << endl;
printTree( t->right );
}else
return;
}
#endif
这是 BinaryNode 结构的代码：
template <class Type>
class BinarySearchTree; //forward declaration so BinaryNode knows about BinarySearchTree
template <class Type>
class BinaryNode{
public:
Type element;
BinaryNode<Type>* left;
BinaryNode<Type>* right;
BinaryNode<Type>* parent;
int priority;
BinaryNode( Type theElement, BinaryNode *lt, BinaryNode* rt, BinaryNode *par = NULL, int pri = 0) :
element(theElement), left(lt), right(rt) , parent(par), priority(pri)
{ }
friend class BinarySearchTree<Type>;
};
有没有人看到我可以改变以提供帮助的任何东西？