leetcode : Add Two Numbers

You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8

Subscribe to see which companies asked this question

/** * Definition for singly-linked list. * public class ListNode { *     int val; *     ListNode next; *     ListNode(int x) { *         val = x; *         next = null; *     } * } */public class Solution {    public ListNode addTwoNumbers(ListNode l1, ListNode l2) {        if(l1 == null && l2 == null) {            return null;        }                    ListNode head = new ListNode(0);        ListNode point = head;        int carry = 0;        while(l1 != null && l2!=null){            int sum = carry + l1.val + l2.val;            point.next = new ListNode(sum % 10);            carry = sum / 10;            l1 = l1.next;            l2 = l2.next;            point = point.next;        }                while(l1 != null) {            int sum =  carry + l1.val;            point.next = new ListNode(sum % 10);            carry = sum /10;            l1 = l1.next;            point = point.next;        }                while(l2 != null) {            int sum =  carry + l2.val;            point.next = new ListNode(sum % 10);            carry = sum /10;            l2 = l2.next;            point = point.next;        }                if (carry != 0) {            point.next = new ListNode(carry);        }        return head.next;    }}