import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args) {
		BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
		try {
			String line = read.readLine();
			String ans = "";

			for (int i = 0; i < line.length(); ++i) {
				if (line.charAt(i) <= 0x5A) {
					ans += (line.charAt(i) + "").toLowerCase();
				} else {
					ans += (line.charAt(i) + "").toUpperCase();
				}
			}

			System.out.println(ans);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}