import static java.lang.Character.*;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String str;
		while ((str = br.readLine()) != null) {
			for (int i = 0; i < str.length(); i++) {
				char c = str.charAt(i);
				if (isLetter(c)) {
					if (isUpperCase(c)) {
						System.out.print(toLowerCase(c));
					} else {
						System.out.print(toUpperCase(c));
					}
				} else {
					System.out.print(c);
				}
			}
			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