import java.util.Scanner;

public class Main {

public static void main(String[] args) {

		//??\??????????????????????????????Scanner???????????§???????????????
		Scanner scan = new Scanner(System.in);

		//???????????????????????????
		String text = scan.nextLine();

		//?????£??????????????\??????????????????
		char[] c = text.toCharArray();

		//??§?????????????°??????????????°???????????????§????????????????????????
		for(int i=0;i< c.length ; i++ ){
			//System.out.println(c[i]);
			if( Character.isLowerCase(c[i])){
				c[i] = Character.toUpperCase(c[i]);
				//System.out.println(c[i]);
			} else {
				c[i] = Character.toLowerCase(c[i]);
				//System.out.println(c[i]);
			}
		}

		//String????????¨?????????
		String s ="";
		//char?????????String?????????1???????????????
		for(int i = 0; i < c.length ; i++ ){
			s += String.valueOf(c[i]);
		}
		//??¨?????¨?????°
		System.out.println(s);


	}

}
/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