import java.util.*;

public class Main {
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        String wrongPass=sc.nextLine();
        
        String pass="";
        for(int i=0;i<wrongPass.length();i++){
            char checkWord=wrongPass.charAt(i);
            if(Character.isUpperCase(checkWord)){
                pass+=String.valueOf(checkWord).toLowerCase();
            }else{
                pass+=String.valueOf(checkWord).toUpperCase();
            }
        }
        System.out.println(pass);
    }
}