import java.util.Scanner;
public class Main {
	public static void main(String[] args){
		Scanner scan=new Scanner(System.in);
		String s=scan.nextLine();
		for(int i=0;i<s.length();i++){
			if(65<=(s.charAt(i))&&(s.charAt(i))<=90){
				System.out.print((char)(s.charAt(i)+32));
			}else if(97<=(s.charAt(i))&&(s.charAt(i))<=122){
				System.out.print((char)(s.charAt(i)-32));
			}else{
				System.out.print(s.charAt(i));
			}
		}
		System.out.println();
		scan.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