Problem 3. Safe Manipulation

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Problem_2.Manipulate_Array
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] arr = Console.ReadLine().Split(' ').ToArray();

            var changeArray = arr;
            var count = 0;

            while (true)
            {
                string commands = Console.ReadLine();

                for (int i = 0; i < arr.Length - 1 ; i++)
                {
                    if (arr[i] == arr[i + 1])
                    {
                        count++;

                    }
                }

                if (commands == "Distinct")
                {
                    if (count > 0)
                    {
                        changeArray = changeArray.Distinct().ToArray();

                    }
                    else
                    {
                        Console.WriteLine("Invalid input!");
                    }

                }
                if (commands == "Reverse")
                {
                    Array.Reverse(changeArray);
                }
                if (commands != "Distinct" && commands != "Reverse" && commands != "END")
                {
                    string[] replace = commands.Split(' ').ToArray();
                    int temp = int.Parse(replace[1]);

                    if (temp >= changeArray.Length || temp < 0 )
                    {
                        Console.WriteLine("Invalid input!");
                        continue;
                    }
                    changeArray[int.Parse(replace[1])] = replace[2];
                }
                if (commands == "END")
                {
                    break;
                }
            }

            Console.WriteLine(string.Join(", ", changeArray));

        }
    }
}