import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner scan = new Scanner(System.in);

		while (true) {
			
			String str = scan.next();
			// strArry????????????????????????????´?
			String[] strArry = str.split("");

			for (int i = 0; i < strArry.length; i++) {

				// strArry[i]?????§??????????°??????????????????????
				// ??????????????????

				if (Character.isUpperCase(strArry[i].charAt(0))) {

					strArry[i] = strArry[i].toLowerCase();

				} else {
					strArry[i] = strArry[i].toUpperCase();
				}

				System.out.print(strArry[i]);

			}
			
			if (scan.hasNext() == false) {
				break;
			}
			
			System.out.print(" ");
		}
		 System.out.println(); 
	}

}
/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