import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		String oldstr = scan.nextLine();
		scan.close();
		String newstr = "";
		//char substr[] = str.toCharArray();
		for(int i = 0; i < oldstr.length(); i++){
			String target = oldstr.substring(i, i + 1);
			if(target.equals(target.toLowerCase())){
				target = target.toUpperCase();
			}else if(target.equals(target.toUpperCase())){
				target = target.toLowerCase();
			}
			newstr += target;
		}
		System.out.println(newstr);
	}
}
/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