我正在研究 AVL 树。树本身似乎正在工作,但我需要一个迭代器来遍历树的值。因此,我尝试实现 IEnumerator 交互。不幸的是,我在实现 IEnumerator 和 IComparable 时遇到编译时错误。首先是代码,然后是错误。
class AvlTreePreOrderEnumerator<T> : IEnumerator<T> where T :IComparable<T>
{
private AvlTreeNode<T> current = default(T);
private AvlTreeNode<T> tree = null;
private Queue<AvlTreeNode<T>> traverseQueue = null;
public AvlTreePreOrderEnumerator(AvlTreeNode<T> tree)
{
this.tree = tree;
//Build queue
traverseQueue = new Queue<AvlTreeNode<T>>();
visitNode(this.tree.Root);
}
private void visitNode(AvlTreeNode<T> node)
{
if (node == null)
return;
else
{
traverseQueue.Enqueue(node);
visitNode(node.LeftChild);
visitNode(node.RightChild);
}
}
public T Current
{
get { return current.Value; }
}
object IEnumerator.Current
{
get { return Current; }
}
public void Dispose()
{
current = null;
tree = null;
}
public void Reset()
{
current = null;
}
public bool MoveNext()
{
if (traverseQueue.Count > 0)
current = traverseQueue.Dequeue();
else
current = null;
return (current != null);
}
}
VS2008 给出的错误:错误 1 类型“T”不能用作泛型类型或方法“Opdr2_AvlTreeTest_Final.AvlTreeNode”中的类型参数“T”。没有从“T”到“System.IComparable”的装箱转换或类型参数转换。
此错误在以下几行中给出:
//members
private AvlTreeNode<T> current = default(T); //current highlighted
private AvlTreeNode<T> tree = null; //tree highlighted
private Queue<AvlTreeNode<T>> traverseQueue = null; //traverseQueue highlighted
//Constructor
public AvlTreePreOrderEnumerator(AvlTreeNode<T> tree) // AvlTreePreOrderEnumerator highlighted
//Method
private void visitNode(AvlTreeNode<T> node) //visitNode highlighted
现在我还没有包含树和节点逻辑。我有人认为有必要解决这个问题,就这么说吧!
谢谢!