| | | 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.DeleteNodesAndReturnForest; |
| | | 15 | | |
| | | 16 | | /// <inheritdoc /> |
| | | 17 | | public class DeleteNodesAndReturnForestDepthFirstSearchRecursive : IDeleteNodesAndReturnForest |
| | | 18 | | { |
| | | 19 | | /// <summary> |
| | | 20 | | /// Time complexity - O(n + d) |
| | | 21 | | /// Space complexity - O(n + d) |
| | | 22 | | /// </summary> |
| | | 23 | | /// <param name="root"></param> |
| | | 24 | | /// <param name="to_delete"></param> |
| | | 25 | | /// <returns></returns> |
| | | 26 | | public IList<TreeNode> DelNodes(TreeNode? root, int[] to_delete) |
| | 8 | 27 | | { |
| | 8 | 28 | | if (root == null) |
| | 1 | 29 | | { |
| | 1 | 30 | | return new List<TreeNode>(); |
| | | 31 | | } |
| | | 32 | | |
| | 7 | 33 | | var result = new List<TreeNode>(); |
| | | 34 | | |
| | 7 | 35 | | var toDeleteHashSet = new HashSet<int>(to_delete); |
| | | 36 | | |
| | 7 | 37 | | DelNodes(root, true, toDeleteHashSet, result); |
| | | 38 | | |
| | 7 | 39 | | return result; |
| | 8 | 40 | | } |
| | | 41 | | |
| | | 42 | | private static TreeNode? DelNodes(TreeNode? node, bool isRoot, IReadOnlySet<int> toDeleteHashSet, |
| | | 43 | | ICollection<TreeNode> result) |
| | 109 | 44 | | { |
| | 109 | 45 | | if (node == null) |
| | 58 | 46 | | { |
| | 58 | 47 | | return null; |
| | | 48 | | } |
| | | 49 | | |
| | 51 | 50 | | var toBeDeleted = toDeleteHashSet.Contains(node.val); |
| | | 51 | | |
| | 51 | 52 | | if (isRoot && !toBeDeleted) |
| | 15 | 53 | | { |
| | 15 | 54 | | result.Add(node); |
| | 15 | 55 | | } |
| | | 56 | | |
| | 51 | 57 | | node.left = DelNodes(node.left, toBeDeleted, toDeleteHashSet, result); |
| | 51 | 58 | | node.right = DelNodes(node.right, toBeDeleted, toDeleteHashSet, result); |
| | | 59 | | |
| | 51 | 60 | | return toBeDeleted ? null : node; |
| | 109 | 61 | | } |
| | | 62 | | } |