Extended version of Binary tree

Question

A node can be binary. Two children. Left and Right.
Example:
A
B C
class Node
   public int data;              // data item (key)
   public Node leftChild; 
   public Node rightChild;  But how would I create a tree with the node can contain as much children?
A
B C R T
and so on? I want to insert a node in A and have it expand each time. Node "A" will contain node {B,C,R,T} for example.
How would I code this?

Answer 1

Much depends on how you see the relation between a Node and it's children. In the simplest form you could just change
class Node
public int data;              // data item (key)
public Node leftChild; 
public Node rightChild;  to
class Node
    public int data;
    public Node[] children;
}or
class Node
    public int data;
    public ArrayList children;
}BUT
what you probably want is for the ordering to be equivalent to
class Node
    public Node leftChild; 
    public int data;              // data item (key)
    public Node rightChild;
} i.e. the data of the current node is sandwiched between that of the left and right nodes.
A BTree is one of the best examples of this (Google is your friend). An approach (and I stress AN) is to have an array of say 'n' values and an array of 'n+1' child nodes with the implied sandwich ordering
[child 0][data0][child 1][data 1] ... [child n][data n][child n+1].
The result is then
class Node
    int[] data = ...;
    Node[] childrean = ...
}where you would dynamically size the 'data' and 'children' arrays and the length of 'children' is always 1 greater than the order of 'data'.