package yukicoder163;
import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner sc=new Scanner(System.in);
		String str=sc.next();
		char[] c=str.toCharArray();
		for(int i=0;i<str.length();i++){
			if(Character.isLowerCase(c[i])){
				System.out.print(Character.toUpperCase(c[i]));
			}else{
				System.out.print(Character.toLowerCase(c[i]));
			}
		}
	}
}