01. String Manipulator - Group 2

using System;
using System.Linq;

namespace _01._Problem
{
    class Program
    {
        static void Main(string[] args)
        {
            string str = Console.ReadLine();
            string line = string.Empty;

            while ((line = Console.ReadLine())!= "Done")
            {
                string command = line.Split(" ")[0];

                if (command == "Change")
                {
                    var ch = line.Split(" ")[1].ToCharArray();
                    var repl = line.Split(" ")[2];
                    str = new string(str.Select(r => r == ch[0] ? (char)(repl[0]) : r).ToArray());
                    Console.WriteLine(str);
                }
                else if (command == "Includes")
                {
                    var isIncluded = line.Split(" ")[1];
                    if (str.Contains(isIncluded))
                    {
                        Console.WriteLine("True");
                    }
                    else
                    {
                        Console.WriteLine("False");
                    }
                }
                else if (command == "End")
                {
                    var endsWith = line.Split(" ")[1];
                    if (str.EndsWith(endsWith))
                    {
                        Console.WriteLine("True");
                    }
                    else
                    {
                        Console.WriteLine("False");
                    }
                }
                else if (command == "Uppercase")
                {
                    str = str.ToUpper();
                    Console.WriteLine(str);
                }
                else if (command == "FindIndex")
                {
                    var ch = line.Split(" ")[1].ToCharArray();
                    Console.WriteLine(str.IndexOf(ch[0]));
                }
                else if (command == "Cut")
                {
                    int startIndex = int.Parse(line.Split(" ")[1]);
                    int length = int.Parse(line.Split(" ")[2]);
                    str = str.Substring(startIndex, length);
                    Console.WriteLine(str);
                }
            }
        }
    }
}