| | | 1 | | // -------------------------------------------------------------------------------- |
| | | 2 | | // Copyright (C) 2025 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.MergeTwoBinaryTrees; |
| | | 15 | | |
| | | 16 | | /// <inheritdoc /> |
| | | 17 | | public class MergeTwoBinaryTreesDepthFirstSearchRecursive : IMergeTwoBinaryTrees |
| | | 18 | | { |
| | | 19 | | /// <summary> |
| | | 20 | | /// Time complexity - O(n + m) |
| | | 21 | | /// Space complexity - O(n + m) for a skewed trees, O(log n + log m) for a balanced trees |
| | | 22 | | /// </summary> |
| | | 23 | | /// <param name="root1"></param> |
| | | 24 | | /// <param name="root2"></param> |
| | | 25 | | /// <returns></returns> |
| | | 26 | | public TreeNode? MergeTrees(TreeNode? root1, TreeNode? root2) |
| | 13 | 27 | | { |
| | 13 | 28 | | if (root1 == null && root2 == null) |
| | 3 | 29 | | { |
| | 3 | 30 | | return null; |
| | | 31 | | } |
| | | 32 | | |
| | 10 | 33 | | if (root1 == null) |
| | 4 | 34 | | { |
| | 4 | 35 | | return root2; |
| | | 36 | | } |
| | | 37 | | |
| | 6 | 38 | | if (root2 == null) |
| | 2 | 39 | | { |
| | 2 | 40 | | return root1; |
| | | 41 | | } |
| | | 42 | | |
| | 4 | 43 | | root1.val += root2.val; |
| | 4 | 44 | | root1.left = MergeTrees(root1.left, root2.left); |
| | 4 | 45 | | root1.right = MergeTrees(root1.right, root2.right); |
| | | 46 | | |
| | 4 | 47 | | return root1; |
| | 13 | 48 | | } |
| | | 49 | | } |