using System;

using System.Collections.Generic;

public class Program

{

    class MyDictionary

    {

        private HashSet<string> hashSet = new();

        public MyDictionary(IEnumerable<string> words)

        {

            foreach(var w in words)

            {

                for(int i=0;i<w.Length;i++)

                {

                    hashSet.Add(w.Substring(0,i) + "*"  + w.Substring(i+1, w.Length-i-1));

                }

                hashSet.Add(w);

            }

        }

        public bool IsInDict(string word)

        {

            return hashSet.Contains(word);

        }

    }

    public static void Main()

    {

        var myDictionary = new MyDictionary(new string[] {"cat", "car", "bar", "bat", "dog", "zebra" });

        Debug.Assert(myDictionary.IsInDict("cat") == true);

        Debug.Assert(myDictionary.IsInDict("don") == false);

        Debug.Assert(myDictionary.IsInDict("caz") == false);

        Debug.Assert(myDictionary.IsInDict("bat") == true);

        Debug.Assert(myDictionary.IsInDict("zebra") == true);

        Debug.Assert(myDictionary.IsInDict("ca*") == true);

        Debug.Assert(myDictionary.IsInDict("c*t") == true);

        Debug.Assert(myDictionary.IsInDict("*at") == true);

        Debug.Assert(myDictionary.IsInDict("da*") == false);

        Debug.Assert(myDictionary.IsInDict("*ag") == false);

    }

    class Debug

    {

        public static void Assert(bool a, [System.Runtime.CompilerServices.CallerLineNumber] int sourceLineNumber = 0)

        {

            if (!a)

            {

                throw new Exception($"Test failed, line {sourceLineNumber}");

            }

        }

    }

}