import java.io.IOException;
import java.util.Scanner;
public class Main {
	public static void main(String[] args) throws IOException{

		Scanner sc = new Scanner(System.in);

		String x = sc.nextLine();
		char[] line = x.toCharArray();

		for(int i=0;i<x.length();i++) {
			if(Character.isUpperCase(line[i])) {
				line[i] = Character.toLowerCase(line[i]);
			}else if(Character.isLowerCase(line[i])) {
				line[i] = Character.toUpperCase(line[i]);
			}
			System.out.print(line[i]);
		}
		System.out.println();
		sc.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