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

class yc2
{
    static void Main()
    {
        string S = Console.ReadLine();
        char[] cs = S.ToCharArray();


        for (int i = 0; i < S.Length; i++)
        {
            if (char.IsLower(cs[i]))
            {
                cs[i] = char.ToUpper(cs[i]);
            }
            else if (char.IsUpper(cs[i]))
            {
                cs[i] = char.ToLower(cs[i]);
            }
            Console.Write(cs[i]);
        }
    }
}