import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = null;

		String anser = "";

		try {
			//??\?????????
			sc = new Scanner(System.in);
			String line = sc.nextLine();

			char[] check = line.toCharArray();

			//?????????????????\????????§??????
			for (int i = 0; i < check.length; i++) {
				if (Character.isUpperCase(check[i])) {
					//?°????????????????
					check[i] = Character.toLowerCase(check[i]);
				}else {
					//??§???????????????
					check[i] = Character.toUpperCase(check[i]);
				}
			}

			System.out.println(check);

		} finally {
			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