Program.cs

string[] lines = File.ReadAllLines("test_words.txt"); // This reads the input coded message from test words
        string decodedMessage = "";

        foreach (string word in lines) // Loops throught the test words file
        {
            if (word == "SPACE") 
            {
                decodedMessage += ' '; // Puts a space in the proper position in output
            }
            else if (word == "COMMA")
            {
                decodedMessage += ','; // Puts a comma in the proper position in output
            }
            else
            {
                if (word.Length > 0) // This is to make sure the word isnt empty
                {
                    decodedMessage += word[0];
                }
                else
                {
                    decodedMessage += ""; // Replace '\0' with an empty string
                }
            }
        }
        Console.WriteLine(decodedMessage); // Prints out the output in the terminal
        File.WriteAllText("decoded.txt", decodedMessage); // Writes the decoded message output to the decoded file