| | | 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.NumberOfSubstringsContainingAllThreeCharacters; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public class NumberOfSubstringsContainingAllThreeCharactersSlidingWindow : |
| | | 16 | | INumberOfSubstringsContainingAllThreeCharacters |
| | | 17 | | { |
| | | 18 | | /// <summary> |
| | | 19 | | /// Time complexity - O(n) |
| | | 20 | | /// Space complexity - O(1) |
| | | 21 | | /// </summary> |
| | | 22 | | /// <param name="s"></param> |
| | | 23 | | /// <returns></returns> |
| | | 24 | | public int NumberOfSubstrings(string s) |
| | 3 | 25 | | { |
| | 3 | 26 | | var numberOfSubstrings = 0; |
| | | 27 | | |
| | 3 | 28 | | var left = 0; |
| | | 29 | | |
| | 3 | 30 | | var frequency = new int[3]; |
| | | 31 | | |
| | 34 | 32 | | for (var right = 0; right < s.Length; right++) |
| | 14 | 33 | | { |
| | 14 | 34 | | frequency[s[right] - 'a']++; |
| | | 35 | | |
| | 22 | 36 | | while (frequency[0] > 0 && frequency[1] > 0 && frequency[2] > 0) |
| | 8 | 37 | | { |
| | 8 | 38 | | numberOfSubstrings += s.Length - right; |
| | | 39 | | |
| | 8 | 40 | | frequency[s[left] - 'a']--; |
| | | 41 | | |
| | 8 | 42 | | left++; |
| | 8 | 43 | | } |
| | 14 | 44 | | } |
| | | 45 | | |
| | 3 | 46 | | return numberOfSubstrings; |
| | 3 | 47 | | } |
| | | 48 | | } |