import java.util.Scanner;

public class No0163{
	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]));
			}
		}
		
		sc.close();
	}
}