C# 3.0 Cookbook, 3rd Edition

11.5. Creating an n-ary Tree

Problem

You need a tree that can store a number of child nodes in each of its nodes. A binary tree will work if each node needs to have only two children, but in this case, each node needs to have a fixed number of child nodes greater than two.

Solution

Use the NTree<T> class shown in Example 11-10 to create the root node for the n-ary tree.

Example 11-10. Generic NTree class

using System;
using System.Collections;
using System.Collections.Generic;

public class NTree<T> : IEnumerable<T>
    where T : IComparable<T>
{
    public NTree()
    {
        maxChildren = int.MaxValue;
    }
    public NTree(int maxNumChildren)
    {
        maxChildren = maxNumChildren;
    }

    // The root node of the tree
    private NTreeNode<T> root = null;
    // The maximum number of child nodes that a parent node may contain
    private int maxChildren = 0;

    public void AddRoot(NTreeNode<T> node)
    {
        root = node;
    }

    public int MaxChildren
    {
        get {return (maxChildren);}
    }
}

The methods defined in Table 11-5are of particular interest to using an NTree<T> object.

Table 11-5. Members of the NTree<T> class

Member	Description
Overloaded constructor	This constructor creates an NTree<T> object. Its syntax is: NTree(int maxNumChildren) where maxNumChildren is the maximum number of children that one node may have at any time.
MaxChildren property	A read-only property to retrieve the maximum number of children any node may have. Its syntax is: int MaxChildren {get;} The value this property returns is set in the constructor.
AddRoot method	Adds a node to ...