| | | 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.VowelSpellchecker; |
| | | 13 | | |
| | | 14 | | /// <inheritdoc /> |
| | | 15 | | public sealed class VowelSpellcheckerDictionary : IVowelSpellchecker |
| | | 16 | | { |
| | | 17 | | /// <summary> |
| | | 18 | | /// Time complexity - O(n * l), where n is the number of words in wordlist and l is the average word length |
| | | 19 | | /// Space complexity - O(n * l), where n is the number of words in wordlist and l is the average word length |
| | | 20 | | /// </summary> |
| | | 21 | | /// <param name="wordlist"></param> |
| | | 22 | | /// <param name="queries"></param> |
| | | 23 | | /// <returns></returns> |
| | | 24 | | public string[] Spellchecker(string[] wordlist, string[] queries) |
| | 2 | 25 | | { |
| | 2 | 26 | | var wordsCount = wordlist.Length; |
| | | 27 | | |
| | 2 | 28 | | var wordsHashSet = new HashSet<string>(wordsCount); |
| | 2 | 29 | | var lowercaseWordsDictionary = new Dictionary<string, string>(wordsCount); |
| | 2 | 30 | | var maskedWordsDictionary = new Dictionary<string, string>(wordsCount); |
| | | 31 | | |
| | 16 | 32 | | foreach (var word in wordlist) |
| | 5 | 33 | | { |
| | 5 | 34 | | wordsHashSet.Add(word); |
| | | 35 | | |
| | 5 | 36 | | var lowercaseWord = GetLowercaseWord(word); |
| | | 37 | | |
| | 5 | 38 | | lowercaseWordsDictionary.TryAdd(lowercaseWord, word); |
| | | 39 | | |
| | 5 | 40 | | var maskedWord = GetMaskedWord(lowercaseWord); |
| | | 41 | | |
| | 5 | 42 | | maskedWordsDictionary.TryAdd(maskedWord, word); |
| | 5 | 43 | | } |
| | | 44 | | |
| | 2 | 45 | | var result = new string[queries.Length]; |
| | | 46 | | |
| | 26 | 47 | | for (var i = 0; i < queries.Length; i++) |
| | 11 | 48 | | { |
| | 11 | 49 | | var query = queries[i]; |
| | | 50 | | |
| | 11 | 51 | | if (wordsHashSet.Contains(query)) |
| | 3 | 52 | | { |
| | 3 | 53 | | result[i] = query; |
| | | 54 | | |
| | 3 | 55 | | continue; |
| | | 56 | | } |
| | | 57 | | |
| | 8 | 58 | | var lowercaseWord = GetLowercaseWord(query); |
| | | 59 | | |
| | 8 | 60 | | if (lowercaseWordsDictionary.TryGetValue(lowercaseWord, out var capMatch)) |
| | 3 | 61 | | { |
| | 3 | 62 | | result[i] = capMatch; |
| | | 63 | | |
| | 3 | 64 | | continue; |
| | | 65 | | } |
| | | 66 | | |
| | 5 | 67 | | var maskedWord = GetMaskedWord(lowercaseWord); |
| | | 68 | | |
| | 5 | 69 | | if (maskedWordsDictionary.TryGetValue(maskedWord, out var vowelMatch)) |
| | 2 | 70 | | { |
| | 2 | 71 | | result[i] = vowelMatch; |
| | 2 | 72 | | } |
| | | 73 | | else |
| | 3 | 74 | | { |
| | 3 | 75 | | result[i] = string.Empty; |
| | 3 | 76 | | } |
| | 5 | 77 | | } |
| | | 78 | | |
| | 2 | 79 | | return result; |
| | 2 | 80 | | } |
| | | 81 | | |
| | | 82 | | private static string GetLowercaseWord(string word) |
| | 13 | 83 | | { |
| | 13 | 84 | | return string.Create(word.Length, word, (span, source) => |
| | 13 | 85 | | { |
| | 138 | 86 | | for (var i = 0; i < source.Length; i++) |
| | 56 | 87 | | { |
| | 56 | 88 | | span[i] = char.ToLowerInvariant(source[i]); |
| | 56 | 89 | | } |
| | 26 | 90 | | }); |
| | 13 | 91 | | } |
| | | 92 | | |
| | | 93 | | private static string GetMaskedWord(string word) |
| | 10 | 94 | | { |
| | 10 | 95 | | Span<char> buffer = stackalloc char[word.Length]; |
| | | 96 | | |
| | 104 | 97 | | for (var i = 0; i < word.Length; i++) |
| | 42 | 98 | | { |
| | 42 | 99 | | var c = word[i]; |
| | | 100 | | |
| | 42 | 101 | | buffer[i] = IsVowel(c) ? '*' : c; |
| | 42 | 102 | | } |
| | | 103 | | |
| | 10 | 104 | | return new string(buffer); |
| | 10 | 105 | | } |
| | | 106 | | |
| | | 107 | | private static bool IsVowel(char c) |
| | 42 | 108 | | { |
| | 42 | 109 | | return c is 'a' or 'e' or 'i' or 'o' or 'u'; |
| | 42 | 110 | | } |
| | | 111 | | } |