import java.io.*;
import java.util.Scanner;

class Main{
	public static void main(String[] args){
		try{
			Scanner stdIn = new Scanner(System.in);
			
			String s = stdIn.nextLine();
			
			int l = s.length();
			for(int i = 0;i < l;i++){
				if(Character.isUpperCase(s.charAt(i))){
					char a = s.charAt(i);
					a = Character.toLowerCase(a);
					System.out.print(a);
				}
				else {
					char a = s.charAt(i);
					a = Character.toUpperCase(a);
					System.out.print(a);
				}
			}
			System.out.println();
		} catch(Exception e){
		}
	}
}
			
/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