https://leetcode.com/problems/add-two-numbers
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order, and each of their nodes contains a single digit. Add the two numbers and return the sum as a linked list.
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
Example 1:
Input: l1 = [2,4,3], l2 = [5,6,4]
Output: [7,0,8]
Explanation: 342 + 465 = 807.
Example 2:
Input: l1 = [0], l2 = [0]
Output: [0]
Example 3:
Input: l1 = [9,9,9,9,9,9,9], l2 = [9,9,9,9]
Output: [8,9,9,9,0,0,0,1]
/**
* Definition for singly-linked list.
* public class ListNode {
* public int val;
* public ListNode next;
* public ListNode(int val=0, ListNode next=null) {
* this.val = val;
* this.next = next;
* }
* }
*/
public class Solution {
public ListNode AddTwoNumbers(ListNode l1, ListNode l2) {
var result = new ListNode();
var l1Next = l1;
var l2Next = l2;
var remainder = 0;
var resultNext = result;
while (l1Next != null || l2Next != null)
{
var sum = (l1Next?.val ?? 0) + (l2Next?.val ?? 0) + remainder;
l1Next = l1Next?.next;
l2Next = l2Next?.next;
resultNext.val = sum % 10;
remainder = sum / 10;
if (l1Next != null || l2Next != null)
resultNext.next = new ListNode();
else
{
if (remainder > 0)
resultNext.next = new ListNode(remainder);
}
resultNext = resultNext.next;
}
return result;
}
}