using System;
public class Program
{
    static void Main()
    {
        string s = Console.ReadLine();
        for (int i = 0; i < s.Length; i++)
        {
            if (Char.IsLower(s, i))
            {
                Console.Write(Char.ToUpper(s[i]));
            }
            else
            {
                Console.Write(Char.ToLower(s[i]));
            }
        }
        Console.WriteLine();
    }
}