using System;
using System.Text;
 
public class Program
{
 
public static void Main(string[] args)
{
    string textString = "Text";
    string codeString = "Code";
 
    var textBuilder = new StringBuilder("Test"); // "Test"
    Console.WriteLine(textBuilder.ToString());
    // simulate the text-button-click:
    textBuilder.Append(textString); // "TestText" 
    Console.WriteLine(textBuilder.ToString());
    // simulate the code-button-click:
    textBuilder.Append(codeString); // "TestTextCode"  
    Console.WriteLine(textBuilder.ToString());
    // simulate the remove-text-button-click:
    textBuilder.Length -= textString.Length; // "TestText"  
    Console.WriteLine(textBuilder.ToString());
    // simulate the remove-code-button-click:
    textBuilder.Length -= codeString.Length; // "Test" 
    Console.WriteLine(textBuilder.ToString());
}
}

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