// class to combine ListNodes into a full linked list

public class LinkedIntList {
   private ListNode front;
   
   public LinkedIntList() {
      front = null;
   }
   
   public void append(int value) {
      // find the last node
      ListNode curr = front;
      while (curr.next != null) {
         curr = curr.next;       
      }
      
      // attach a new node to the last node
      ListNode temp = new ListNode();
      temp.data = value;
      curr.next = temp;
   }
}