import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String line = sc.nextLine();
		String ans = "";
		for (int i = 0; i < line.length(); i++) {
			char c = line.charAt(i);
			if (Character.isLowerCase(c)) {
				ans += Character.toUpperCase(c);
			} else {
				ans += Character.toLowerCase(c);
			}
		}
		System.out.println(ans);
		sc.close();
	}

}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz