using System;
using System.Linq;
using System.Collections.Generic;

namespace test20190423
{
    class Program
    {
        static void Main(string[] args)
        {
            var ret = "";
            Console.ReadLine().ToCharArray().ToList().ForEach(x => 
            {
                if ('a' <= x && x <= 'z') ret += x.ToString().ToUpper();
                else ret += x.ToString().ToLower();
            });
            Console.WriteLine(ret);
            Console.ReadLine();
        }
    }
}