LINQ and HashSet approach in C#
\n\n# Code\n\npublic class Solution {\n    public int CountConsistentStrings(string allowed, string[] words)\n    {\n        var hashSet = new HashSet<char>(all
\n\n# Code\n```\npublic class Solution {\n    public int CountConsistentStrings(string allowed, string[] words)\n    {\n        var hashSet = new HashSet<char>(allowed);\n\n        return words.Count(word => word.All(c => hashSet.Contains(c)));\n    }\n}\n```
['C#']