using System;

namespace Ex160426_1{
    public class Program{
        public static void Main(string[] args){
            var str = Console.ReadLine().ToCharArray();
            for(var i = 0; i < str.Length; i++)
                if(char.IsUpper(str[i])) str[i] = char.ToLower(str[i]);
                else str[i] = char.ToUpper(str[i]);
            Console.WriteLine(str);
        }
    }
}