import java.io.*;

class Main {
	public static void main(String[] args) throws IOException {

		BufferedReader input = new BufferedReader (new InputStreamReader(System.in));
		String str = input.readLine();

		for (int i = 0; i < str.length(); i++) {

			if (Character.isLowerCase(str.charAt(i)))
				System.out.print(Character.toUpperCase(str.charAt(i)));
			else
				System.out.print(Character.toLowerCase(str.charAt(i)));
		}
		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