using System;

namespace PracticeAtCoder
{
    class Program
    {
        static void Main(string[] args)
        {
            var inputIntArray = Console.ReadLine();
            var counter = 0;
            String str = "";
            String s1 = "";
            String s2 = "";
            foreach(var a in inputIntArray)
            {
					/*
					s2 = "" + a;
					s2 = s2.ToUpper();
					s1　=　s1+ "" + s2;
				*/
            	if (char.IsUpper(a)) {
            		//char -> String 変換
					s2 = "" + a;
					s2 = s2.ToLower();
					s1　=　s1+ "" + s2;
            		
            		
            	}else if(char.IsLower(a)){
            		
            		//char -> String 変換
					s2 = "" + a;
					s2 = s2.ToUpper();
					s1　=　s1+ "" + s2;
            	}
				
        
            }
            	Console.WriteLine(s1);
        }
    }
}