| | | 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 | | namespace LeetCode.Algorithms.PushDominoes; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public sealed class PushDominoesTwoPointers : IPushDominoes |
| | | 16 | | { |
| | | 17 | | /// <summary> |
| | | 18 | | /// Time complexity - O(n) |
| | | 19 | | /// Space complexity - O(n) |
| | | 20 | | /// </summary> |
| | | 21 | | /// <param name="dominoes"></param> |
| | | 22 | | /// <returns></returns> |
| | | 23 | | public string PushDominoes(string dominoes) |
| | 2 | 24 | | { |
| | 2 | 25 | | var dominoesCharArray = dominoes.ToCharArray(); |
| | | 26 | | |
| | 2 | 27 | | var left = -1; |
| | | 28 | | |
| | 44 | 29 | | for (var right = 0; right <= dominoesCharArray.Length; right++) |
| | 20 | 30 | | { |
| | 20 | 31 | | var current = right < dominoesCharArray.Length ? dominoesCharArray[right] : 'R'; |
| | 20 | 32 | | var previous = left >= 0 ? dominoesCharArray[left] : 'L'; |
| | | 33 | | |
| | 20 | 34 | | if (current == '.') |
| | 10 | 35 | | { |
| | 10 | 36 | | continue; |
| | | 37 | | } |
| | | 38 | | |
| | 10 | 39 | | if (right - left > 1) |
| | 6 | 40 | | { |
| | 6 | 41 | | var currentLeft = left + 1; |
| | 6 | 42 | | var currentRight = right - 1; |
| | | 43 | | |
| | 6 | 44 | | if (previous == current) |
| | 1 | 45 | | { |
| | 2 | 46 | | while (currentLeft <= currentRight) |
| | 1 | 47 | | { |
| | 1 | 48 | | dominoesCharArray[currentLeft] = current; |
| | | 49 | | |
| | 1 | 50 | | currentLeft++; |
| | 1 | 51 | | } |
| | 1 | 52 | | } |
| | 5 | 53 | | else if (previous == 'R' && current == 'L') |
| | 3 | 54 | | { |
| | 5 | 55 | | while (currentLeft < currentRight) |
| | 2 | 56 | | { |
| | 2 | 57 | | dominoesCharArray[currentLeft] = 'R'; |
| | 2 | 58 | | dominoesCharArray[currentRight] = 'L'; |
| | | 59 | | |
| | 2 | 60 | | currentLeft++; |
| | 2 | 61 | | currentRight--; |
| | 2 | 62 | | } |
| | 3 | 63 | | } |
| | 6 | 64 | | } |
| | | 65 | | |
| | 10 | 66 | | left = right; |
| | 10 | 67 | | } |
| | | 68 | | |
| | 2 | 69 | | return new string(dominoesCharArray); |
| | 2 | 70 | | } |
| | | 71 | | } |