Write the code necessary to convert the following sequence of listnode objects:

list -> [1] - [2] /
into this sequence of listnode objects:

list -> [3] -> [1] -> [2] /
assume that you are using listnode class as defined below:

public class listnode {
public int data; // data stored in this node
public listnode next; // a link to the next node in the list

public listnode() { }
public listnode(int data) { }
public listnode(int data, listnode next) { }
}