数据结构与算法(C#实现)N叉树

using System;
using System.Collections;

namespace DataStructure
{
/// <summary>
/// NaryTree 的摘要说明。-----N叉树
/// </summary>
public class NaryTree:Tree
{
// member variables
protected object key;
protected uint degree;
protected ArrayList treeList=new ArrayList();
//protected uint height=0;//暂时默认为0

//create an empty tree whose attribute of degree is _degree
public NaryTree(uint _degree)
{
//
// TODO: 在此处添加构造函数逻辑
//
this.key=null;
this.degree=_degree;
this.treeList=null;
}
//构造一棵叶子结点的N叉树
public NaryTree(uint _degree,object _key)
{
this.key=_key;
this.degree=_degree;
this.treeList=new ArrayList();
this.treeList.Capacity=(int)_degree;

for(int i=0;i<this.treeList.Capacity;i++)
{

this.treeList.Add( thisl.GetEmptyInstance(_degree) );

}
}
//-----------------------------------------------------------------
protected virtual object GetEmptyInstance(uint _degree)
{ return new NaryTree(_degree); }
//-------------------------------------------------------------------
//judge whether the tree is an empty tree
public override bool IsEmpty()
{ return this.key==null; }
//判定是否是叶子结点。如果即不是空树且每一棵子树均为空树，则为叶子结点
public override bool IsLeaf()
{
if(IsEmpty())
return false;
for(uint i=0;i<this.degree;i++)
{
if( !(this[i].IsEmpty()) )
return false;
}
return true;
}
//-----------------------------------Inherited Attributes---------------------------------
public override object Key
{
get
{
return this.key;
}
}
//索引器
public override Tree this[uint _index]
{

get

{

if( _index>=this.degree )
throw new Exception("My:out of index!");//如果出界，则抛出异常
if( this.IsEmpty() )
return null;//如果是空树，则索引器返回一个 null
return (Tree)this.treeList[(int)_index];
}
set
{
this.treeList[(int)_index]=value;
}
}