add nodes in linked list.txt

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {   
    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
        if(l1==null) return l2;
        if(l2==null) return l1;
        ListNode c1=l1;
        ListNode c2=l2;
        ListNode dummy = new ListNode(-1);
        ListNode temp=dummy;
        int carry=0;
        while(c1!=null)
        {
            int d=c1.val+(c2 != null ? c2.val : 0)+carry;
            temp.next=new ListNode(d%10);
            temp=temp.next;
            carry=d/10;
            c1=c1.next;
            if(c2!=null) c2=c2.next;
        }        
        while(c2!=null)
        {
            int d=c2.val+carry;
            temp.next=new ListNode(d%10);
            temp=temp.next;
            carry=d/10;
            c2=c2.next;
        }
        if(carry!=0)
        {
            temp.next=new ListNode(carry);
            temp=temp.next;
        }
        return (dummy.next);
    }
}