import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();
		// split??§????????????????´?
		String[] strArray = str.split("");
		//String[] strArray = new String[str.length()]; 
		
		for (int i = 0; i < strArray.length; i++) {
			if(Character.isUpperCase(str.charAt(i))){
				//??§???????????¨???
				strArray[i] = strArray[i].toLowerCase();
			}else{
				strArray[i] = strArray[i].toUpperCase();
			}
		    System.out.print(strArray[i]);
		}
		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