using System;
using System.Collections.Generic;
namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
#if LocalDebug
            var exStdIn = new System.IO.StreamReader("stdin.txt");
            System.Console.SetIn(exStdIn);
#endif
            var Input = Console.ReadLine();
            string Output = "";

            foreach (var n in Input)
            {
                Output += (char.IsLower(n)) ? char.ToUpper(n) : char.ToLower(n);
            }

            Console.WriteLine(Output);

#if LocalDebug
            System.Console.ReadKey();
#endif
        }




        static int GetData()
        {
            return int.Parse(Console.ReadLine());
        }

        static string[] GetList()
        {
            return Console.ReadLine().Split(' ');
        }



    }
}