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

namespace yukicoder
{
    class Program
    {
        static void Main(string[] args)
        {
            string s = Console.ReadLine();
            
            Console.WriteLine(strix(s));
        }

        static string strix(string str)
        {
            int size = str.Length;
            char tmp;
            string ans = "";
            for(int i = 0; i < size; i++)
            {
                tmp = str[i];
                if (Char.IsUpper(tmp))
                {
                    ans += tmp.ToString().ToLower();
                }
                else
                {
                    ans += tmp.ToString().ToUpper();
                }
                
            }

            return ans;
        }

    }
}