import java.util.Scanner;

class Caps {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str = in.next();
        int n = str.length();
        String caps = "";
        for(int i = 0; i < n; i++) {
            if(Character.isUpperCase(str.charAt(i))) {
                caps += Character.toLowerCase(str.charAt(i));
            } else {
                caps += Character.toUpperCase(str.charAt(i));
            }
        }
        System.out.println(caps);
    }
}