| | | 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 | | namespace LeetCode.Algorithms.MaximumSwap; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public class MaximumSwapGreedy : IMaximumSwap |
| | | 16 | | { |
| | | 17 | | /// <summary> |
| | | 18 | | /// Time complexity - O(n) |
| | | 19 | | /// Space complexity - O(n) |
| | | 20 | | /// </summary> |
| | | 21 | | /// <param name="num"></param> |
| | | 22 | | /// <returns></returns> |
| | | 23 | | public int MaximumSwap(int num) |
| | 2 | 24 | | { |
| | 2 | 25 | | var digits = num.ToString().ToCharArray(); |
| | | 26 | | |
| | 2 | 27 | | var last = new int[10]; |
| | | 28 | | |
| | 20 | 29 | | for (var i = 0; i < digits.Length; i++) |
| | 8 | 30 | | { |
| | 8 | 31 | | last[digits[i] - '0'] = i; |
| | 8 | 32 | | } |
| | | 33 | | |
| | 12 | 34 | | for (var i = 0; i < digits.Length; i++) |
| | 5 | 35 | | { |
| | 30 | 36 | | for (var d = 9; d > digits[i] - '0'; d--) |
| | 11 | 37 | | { |
| | 11 | 38 | | if (last[d] <= i) |
| | 10 | 39 | | { |
| | 10 | 40 | | continue; |
| | | 41 | | } |
| | | 42 | | |
| | 1 | 43 | | (digits[i], digits[last[d]]) = (digits[last[d]], digits[i]); |
| | | 44 | | |
| | 1 | 45 | | return int.Parse(new string(digits)); |
| | | 46 | | } |
| | 4 | 47 | | } |
| | | 48 | | |
| | 1 | 49 | | return num; |
| | 2 | 50 | | } |
| | | 51 | | } |