using System;
using System.Text;

class Program
{
    static void Main(string[] args)
    {
        string line = System.Console.ReadLine().Trim();

        StringBuilder sb = new StringBuilder();

        for(int i=0;i<line.Length;i++)
        {
            char c = line[i];
            string s = c.ToString();
            

            if (char.IsLower(c))
            {
                sb.Append(s.ToUpper());
            }
            else
            {
                sb.Append(s.ToLower());
            }
        }
        System.Console.WriteLine(sb);
    }
}