using System;

class Program
{
	static void Main ()
	{
		char[] str = Console.ReadLine ().ToCharArray ();
		foreach (var c in str)
		{
			if (Char.IsUpper (c))
				Console.Write (char.ToLower (c));
			else
				Console.Write (char.ToUpper (c));
		}
		Console.WriteLine ();
	}
}