Add digits stored in linklist nodes.The digits are in reverse order Eg: Add 354 and 445 L1 : ->4->5->3->null L2 : ->5->4->4->null Ans : ->9->9->7->null

 class Node{  
      public int data;  
      public Node next;  
      public Node(int n){  
           this.data = n;  
           this.next = null;  
      }  
 }  
 public class LinkList{  
      public Node addNode(Node head, int n){  
           if(head == null){  
                head = new Node(n);  
                return head;  
           }  
           Node curr = head;  
           while(curr.next != null){  
                curr = curr.next;  
           }  
           curr.next= new Node(n);  
           return head;  
      }  
      public static void printLinkList(Node head){  
           if(head == null){  
                return;  
           }  
           Node curr = head;  
           while(curr != null){  
                System.out.print("->"+curr.data);  
                curr = curr.next;  
           }  
           System.out.print("->null");  
           System.out.println();  
      }  
      public static Node addLists(Node head1, Node head2){  
           if(head1==null && head2==null){  
                return null;  
           }else if(head1 == null){  
                return head2;  
           }else if(head2 == null){  
                return head1;  
           }  
           Node newHead = null;  
           Node newCurr = null;  
           Node curr1 = head1;  
           Node curr2 = head2;  
           int carry = 0;  
           while(curr1 != null && curr2 != null){  
                int newSum = curr1.data + curr2.data + carry;  
                if(newSum >= 10){  
                     carry = 1;  
                     newSum = newSum - 10;  
                }else{  
                     carry = 0;  
                }  
                if(newHead == null){//first node  
                     newHead = new Node(newSum);  
                     newCurr = newHead;  
                }else{//subsequent nodes  
                     newCurr.next = new Node(newSum);  
                     newCurr = newCurr.next;  
                }  
                curr1= curr1.next;  
                curr2= curr2.next;  
           }  
           while(curr1 != null){  
                int newSum = curr1.data + carry;  
                if(newSum >= 10){  
                     carry = 1;  
                     newSum = newSum - 10;  
                }else{  
                     carry = 0;  
                }  
                newCurr.next = new Node(newSum);  
                newCurr = newCurr.next;  
                curr1= curr1.next;  
           }  
           while(curr2 != null){  
                int newSum = curr2.data + carry;  
                if(newSum >= 10){  
                     carry = 1;  
                     newSum = newSum - 10;  
                }else{  
                     carry = 0;  
                }  
                newCurr.next = new Node(newSum);  
                newCurr = newCurr.next;  
                curr2= curr2.next;  
           }  
           if(carry == 1){  
                newCurr.next = new Node(1);  
                newCurr = newCurr.next;  
           }  
           newCurr.next = null;  
           return newHead;  
      }  
      public static void main(String args[]){  
           LinkList l1 = new LinkList();  
           Node head1 = l1.addNode(null, 1);  
           head1 = l1.addNode(head1, 2);  
           head1 = l1.addNode(head1, 6);  
           head1 = l1.addNode(head1, 9);  
           LinkList l2 = new LinkList();  
           Node head2 = l2.addNode(null, 4);  
           head2 = l2.addNode(head2, 5);  
           head2 = l2.addNode(head2, 5);  
           LinkList.printLinkList(head1);  
           LinkList.printLinkList(head2);  
           Node head3 = LinkList.addLists(head1, head2);  
           LinkList.printLinkList(head3);  
      }  
 }