| | | 1 | | // -------------------------------------------------------------------------------- |
| | | 2 | | // Copyright (C) 2026 Eugene Eremeev (also known as Yevhenii Yeriemeieiv). |
| | | 3 | | // All Rights Reserved. |
| | | 4 | | // -------------------------------------------------------------------------------- |
| | | 5 | | // This software is the confidential and proprietary information of Eugene Eremeev |
| | | 6 | | // (also known as Yevhenii Yeriemeieiv) ("Confidential Information"). You shall not |
| | | 7 | | // disclose such Confidential Information and shall use it only in accordance with |
| | | 8 | | // the terms of the license agreement you entered into with Eugene Eremeev (also |
| | | 9 | | // known as Yevhenii Yeriemeieiv). |
| | | 10 | | // -------------------------------------------------------------------------------- |
| | | 11 | | |
| | | 12 | | using LeetCode.Core.Models; |
| | | 13 | | |
| | | 14 | | namespace LeetCode.Algorithms.AddTwoNumbers2; |
| | | 15 | | |
| | | 16 | | /// <inheritdoc /> |
| | | 17 | | public sealed class AddTwoNumbers2Reverse : IAddTwoNumbers2 |
| | | 18 | | { |
| | | 19 | | /// <summary> |
| | | 20 | | /// Time complexity - O(n + m) |
| | | 21 | | /// Space complexity - O(n + m) |
| | | 22 | | /// </summary> |
| | | 23 | | /// <param name="l1"></param> |
| | | 24 | | /// <param name="l2"></param> |
| | | 25 | | /// <returns></returns> |
| | | 26 | | public ListNode AddTwoNumbers(ListNode l1, ListNode l2) |
| | 3 | 27 | | { |
| | 3 | 28 | | var dummyNode = new ListNode(); |
| | 3 | 29 | | var node = dummyNode; |
| | | 30 | | |
| | 3 | 31 | | var l1Node = Reverse(l1); |
| | 3 | 32 | | var l2Node = Reverse(l2); |
| | | 33 | | |
| | 3 | 34 | | var remainder = 0; |
| | | 35 | | |
| | 11 | 36 | | while (l1Node != null || l2Node != null || remainder > 0) |
| | 8 | 37 | | { |
| | 8 | 38 | | var value = remainder; |
| | | 39 | | |
| | 8 | 40 | | if (l1Node != null) |
| | 8 | 41 | | { |
| | 8 | 42 | | value += l1Node.val; |
| | | 43 | | |
| | 8 | 44 | | l1Node = l1Node.next; |
| | 8 | 45 | | } |
| | | 46 | | |
| | 8 | 47 | | if (l2Node != null) |
| | 7 | 48 | | { |
| | 7 | 49 | | value += l2Node.val; |
| | | 50 | | |
| | 7 | 51 | | l2Node = l2Node.next; |
| | 7 | 52 | | } |
| | | 53 | | |
| | 8 | 54 | | if (value > 9) |
| | 2 | 55 | | { |
| | 2 | 56 | | remainder = 1; |
| | 2 | 57 | | value -= 10; |
| | 2 | 58 | | } |
| | | 59 | | else |
| | 6 | 60 | | { |
| | 6 | 61 | | remainder = 0; |
| | 6 | 62 | | } |
| | | 63 | | |
| | 8 | 64 | | node.next = new ListNode(value); |
| | 8 | 65 | | node = node.next; |
| | 8 | 66 | | } |
| | | 67 | | |
| | 3 | 68 | | return Reverse(dummyNode.next); |
| | 3 | 69 | | } |
| | | 70 | | |
| | | 71 | | private static ListNode Reverse(ListNode? node) |
| | 9 | 72 | | { |
| | 9 | 73 | | ListNode? prev = null; |
| | | 74 | | |
| | 32 | 75 | | while (node != null) |
| | 23 | 76 | | { |
| | 23 | 77 | | var next = node.next; |
| | 23 | 78 | | node.next = prev; |
| | 23 | 79 | | prev = node; |
| | 23 | 80 | | node = next; |
| | 23 | 81 | | } |
| | | 82 | | |
| | 9 | 83 | | return prev!; |
| | 9 | 84 | | } |
| | | 85 | | } |