import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Scanner;
public class Main {
	public static void main(String[] args) throws IOException {
		Scanner stdIn = new Scanner(System.in);
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String A = br.readLine();
		char[] B = A.toCharArray();
		
		
		for(int i = 0; i < B.length; i++) {
			if(Character.isLowerCase(B[i])) {
				B[i] = Character.toUpperCase(B[i]);
			}
			else if (Character.isUpperCase(B[i])) {
				B[i] = Character.toLowerCase(B[i]);
			}
		}
		
		A = new String(B);
		
		System.out.println(A);
	}
}
/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