/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
		BufferedReader br =
        new BufferedReader(new InputStreamReader(System.in));
        
        String line = br.readLine();
		String ans = "";
        
    	for (int i = 0; i < line.length(); i++) {
    		String s = line.substring(i, i+1);
    		if (s.equals(s.toUpperCase())) {
    			ans += s.toLowerCase();
    		}
    		else {
    			ans += s.toUpperCase();
    		}
    	}   
    	
    	System.out.println(ans);
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz