import java.util.Scanner;
class Main{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String str = sc.next();
		char[] c = str.toCharArray();
		for(char ch:c) {
			if(Character.isLowerCase(ch)) {
				System.out.print(Character.toUpperCase(ch));
			}else if(Character.isUpperCase(ch)) {
				System.out.print(Character.toLowerCase(ch));
			}
		}
		System.out.println("");
	}
}