import java.util.Scanner;

public class No163 {
	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 < c.length; i++){
			if(Character.isLowerCase(c[i])){
				System.out.println(Character.toUpperCase(c[i]));
			} else {
				System.out.println(Character.toLowerCase(c[i]));
			}
		}

		sc.close();

		}
}