import java.util.Scanner;

class Yukicoder {
    static public void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        StringBuilder S = new StringBuilder();
        S.append(scanner.next());

        if (S.length() < 1 || S.length() > 100) System.exit(1);

        char tmp;
        for (int i = 0; i < S.length(); i++) {
            tmp = S.charAt(i);
            if (Character.isLowerCase(tmp)) tmp = Character.toUpperCase(tmp);
            else tmp = Character.toLowerCase(tmp);
            S.setCharAt(i, tmp);
        }

        System.out.println(S);
    }
}