using System;

public class Program

{

    public static void Main()

    {

        string str = Console.ReadLine();

        string final = "";

        char store;

        char[] a = str.ToCharArray();

        for (int i = 0; i < a.Length; ++i)

        {

            char letter = a[i];

            if(char.IsLower(a[i]))

                store = char.ToUpper(letter);

            else

                store = char.ToLower(letter);

            final += store;         

        }       

        Console.WriteLine("{0}", final);

    }

}