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

namespace SortItems
{
    class Program
    {
        static void Main(string[] args)
        {
            var s = Console.ReadLine();
            var ans = "";

            for (var i = 0; i < s.Length; i++)
            {
                if (char.IsUpper(s[i]))
                {
                    ans += char.ToLower(s[i]);
                }
                else
                {
                    ans += char.ToUpper(s[i]);
                }
            }

            Console.WriteLine(ans);
        }
    }
}