| | | 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.FindingPairsWithCertainSum; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public class FindingPairsWithCertainSumDictionary : IFindingPairsWithCertainSum |
| | | 16 | | { |
| | | 17 | | private readonly int[] _nums1; |
| | | 18 | | private readonly int[] _nums2; |
| | | 19 | | private readonly Dictionary<int, int> _nums2FrequencyDictionary; |
| | | 20 | | |
| | | 21 | | /// <summary> |
| | | 22 | | /// Time complexity - O(n) |
| | | 23 | | /// Space complexity - O(n) |
| | | 24 | | /// </summary> |
| | | 25 | | /// <param name="nums1"></param> |
| | | 26 | | /// <param name="nums2"></param> |
| | 1 | 27 | | public FindingPairsWithCertainSumDictionary(int[] nums1, int[] nums2) |
| | 1 | 28 | | { |
| | 1 | 29 | | _nums1 = nums1; |
| | 1 | 30 | | _nums2 = nums2; |
| | 1 | 31 | | _nums2FrequencyDictionary = new Dictionary<int, int>(); |
| | | 32 | | |
| | 15 | 33 | | foreach (var num2 in nums2) |
| | 6 | 34 | | { |
| | 6 | 35 | | if (!_nums2FrequencyDictionary.TryAdd(num2, 1)) |
| | 2 | 36 | | { |
| | 2 | 37 | | _nums2FrequencyDictionary[num2]++; |
| | 2 | 38 | | } |
| | 6 | 39 | | } |
| | 1 | 40 | | } |
| | | 41 | | |
| | | 42 | | /// <summary> |
| | | 43 | | /// Time complexity - O(1) |
| | | 44 | | /// Space complexity - O(1) |
| | | 45 | | /// </summary> |
| | | 46 | | /// <param name="index"></param> |
| | | 47 | | /// <param name="val"></param> |
| | | 48 | | public void Add(int index, int val) |
| | 3 | 49 | | { |
| | 3 | 50 | | _nums2FrequencyDictionary[_nums2[index]]--; |
| | | 51 | | |
| | 3 | 52 | | if (_nums2FrequencyDictionary[_nums2[index]] == 0) |
| | 2 | 53 | | { |
| | 2 | 54 | | _nums2FrequencyDictionary.Remove(_nums2[index]); |
| | 2 | 55 | | } |
| | | 56 | | |
| | 3 | 57 | | _nums2[index] += val; |
| | | 58 | | |
| | 3 | 59 | | if (!_nums2FrequencyDictionary.TryAdd(_nums2[index], 1)) |
| | 2 | 60 | | { |
| | 2 | 61 | | _nums2FrequencyDictionary[_nums2[index]]++; |
| | 2 | 62 | | } |
| | 3 | 63 | | } |
| | | 64 | | |
| | | 65 | | /// <summary> |
| | | 66 | | /// Time complexity - O(n) |
| | | 67 | | /// Space complexity - O(1) |
| | | 68 | | /// </summary> |
| | | 69 | | /// <param name="tot"></param> |
| | | 70 | | /// <returns></returns> |
| | | 71 | | public int Count(int tot) |
| | 4 | 72 | | { |
| | 4 | 73 | | var count = 0; |
| | | 74 | | |
| | 60 | 75 | | foreach (var num1 in _nums1) |
| | 24 | 76 | | { |
| | 24 | 77 | | if (_nums2FrequencyDictionary.TryGetValue(tot - num1, out var value)) |
| | 10 | 78 | | { |
| | 10 | 79 | | count += value; |
| | 10 | 80 | | } |
| | 24 | 81 | | } |
| | | 82 | | |
| | 4 | 83 | | return count; |
| | 4 | 84 | | } |
| | | 85 | | } |