Day 021-Add Two Numbers

// ( --- https://leetcode.com/problems/add-two-numbers/submissions/ --- )


// 2. Add Two Numbers


/**
 * 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) {
        int c = 0, sum, d1, d2;
        ListNode head = new ListNode(0), temp = null;
        ListNode ans = head;
        
        while(l1!=null || l2!=null || c>0) {
            if(l1!=null){
                d1 = l1.val;
                l1 = l1.next;
            } else {
                d1 = 0;
            }
            if(l2!=null){
                d2 = l2.val;
                l2 = l2.next;
            } else {
                d2 = 0;
            }
            temp = new ListNode((d1+d2+c)%10);
           
            ans.next = temp;
            ans = ans.next;
            c = d1+d2+c>=10? 1 : 0;
        }
        return head.next;
    }
}