| | | 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.FindBottomLeftTreeValue; |
| | | 15 | | |
| | | 16 | | /// <inheritdoc /> |
| | | 17 | | public class FindBottomLeftTreeValueDepthFirst : IFindBottomLeftTreeValue |
| | | 18 | | { |
| | | 19 | | /// <summary> |
| | | 20 | | /// Time complexity - O(n) |
| | | 21 | | /// Space complexity - O(log n) for a balanced tree, O(n) for a skewed tree |
| | | 22 | | /// </summary> |
| | | 23 | | /// <param name="root"></param> |
| | | 24 | | /// <returns></returns> |
| | | 25 | | public int FindBottomLeftValue(TreeNode? root) |
| | 5 | 26 | | { |
| | 5 | 27 | | return root == null ? 0 : FindBottomLeftValue(root, 0).Item1; |
| | 5 | 28 | | } |
| | | 29 | | |
| | | 30 | | private static (int, int) FindBottomLeftValue(TreeNode root, int lastRow) |
| | 22 | 31 | | { |
| | 22 | 32 | | if (root.left == null && root.right == null) |
| | 10 | 33 | | { |
| | 10 | 34 | | return (root.val, lastRow); |
| | | 35 | | } |
| | | 36 | | |
| | 12 | 37 | | var leftValue = (0, 0); |
| | | 38 | | |
| | 12 | 39 | | if (root.left != null) |
| | 10 | 40 | | { |
| | 10 | 41 | | leftValue = FindBottomLeftValue(root.left, lastRow + 1); |
| | 10 | 42 | | } |
| | | 43 | | |
| | 12 | 44 | | var rightValue = (0, 0); |
| | | 45 | | |
| | 12 | 46 | | if (root.right != null) |
| | 8 | 47 | | { |
| | 8 | 48 | | rightValue = FindBottomLeftValue(root.right, lastRow + 1); |
| | 8 | 49 | | } |
| | | 50 | | |
| | 12 | 51 | | return leftValue.Item2 >= rightValue.Item2 ? leftValue : rightValue; |
| | 22 | 52 | | } |
| | | 53 | | } |