AddTwoNumbers.cs

// Source : https://leetcode.com/problems/add-two-numbers/
// Author : codeyu
// Date : 2016-09-19

/********************************************************************************** 
* 
* 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
* 
**********************************************************************************/
using Algorithms.Utils;
namespace Algorithms
{
 public class Solution002 
 {
 public static ListNode<int> AddTwoNumbers(ListNode<int> l1, ListNode<int> l2)
 {
 ListNode<int> head = new ListNode<int>(0);
 ListNode<int> current = head;
 var carry = 0;
 while (l1 != null || l2 != null)
 {
 var x = l1 != null ? l1.Val : 0;
 var y = l2 != null ? l2.Val : 0;
 var digit = carry + x + y;
 carry = digit /10;
 current.Next = new ListNode<int>(digit%10);
 current = current.Next;
 if(l1 != null) { l1 = l1.Next;}
 if(l2 != null) { l2 = l2.Next;}
 }
 if(carry > 0){ current.Next = new ListNode<int>(carry); }
 return head.Next;
 }
 
 }
}