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

namespace Task4
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter a String : ");
            string input = Console.ReadLine().ToUpper();

            char[] inputarray = input.ToArray();
            String alphabets = "ABCDEFGHIJKLMNOPQRSTUVYXWZ";
            String cipherAlphabtes = "DEFGHIJKLMNOPQRSTUVWXYZABC";

            Console.WriteLine("Applying Caesar cipher");


                        String cipherText = "";

            foreach (char letters in inputarray)
            {
                int pos = alphabets.IndexOf(letters);
                if (pos >= 0)
                {
                    cipherText += cipherAlphabtes[pos];
                }
            }

            Console.WriteLine("Plain Text = " + input);
            Console.WriteLine("Cipher Text = " + cipherText);
            Console.ReadKey();
        }
    }
}