P01.Activation_Keys (C# Shell App Paste)

//Disclaimer: The creator of 'C# Shell (C# Offline Compiler)' is in no way responsible for the code posted by any user.
using System;
using System.IO;
using System.Linq;
using System.Collections.Generic;

namespace CSharp_Shell
{

    public static class Program
    {
        public static void Main()
        {
            var raw = Console.ReadLine();
            var substring = String.Empty;
            while(true)
            {
                var input = Console.ReadLine();
                if(input=="Generate")
                {
                    break;
                }
                var command  = input.Split(">>>");
                if(command[0] == "Contains")
                {
                    substring = command[1];
                    if(raw.Contains(substring))
                    {
                        Console.WriteLine($"{raw} contains {substring}");
                    }
                    else
                    {
                        Console.WriteLine("Substring not found!");
                    }
                }
                if(command[0] == "Flip")
                {

                    if(command[1] == "Upper")
                    {

                        var startIndex = int.Parse(command[2]);
                        var endIndex = int.Parse(command[3]);
                        var length = endIndex-startIndex;
                        substring = raw.Substring(startIndex, length);
                        var curr = raw.Replace(substring, substring.ToUpper());
                        raw = curr;
                        Console.WriteLine(raw);

                    }
                    if(command[1] == "Lower")
                    {
                        var startIndex = int.Parse(command[2]);
                        var endIndex = int.Parse(command[3]);
                        var length = endIndex - startIndex;
                        substring = raw.Substring(startIndex, length);
                        var curr = raw.Replace(substring, substring.ToLower());
                        raw = curr;
                        Console.WriteLine(raw);

                    }
                }
                if(command[0] == "Slice")
                {
                    var startIndex = int.Parse(command[1]);
                    var endIndex = int.Parse(command[2]);
                    var length = endIndex - startIndex;
                    var curr = raw.Remove(startIndex, length);
                    raw = curr;
                    Console.WriteLine(raw);
                }

           }
           Print(raw);
        }
        public static void Print(string raw)
        {
            Console.WriteLine($"Your activation key is: {raw}");
        }
    }
}