

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));
		// input
		String tempStr= br.readLine();//clear

		// Constraints

	/*	for (int i = 0; i < tempStr.length(); i++){
			String str;
			if(tempStr.charAt(i) >= 'a' && tempStr.charAt(i) <= 'z') {
				str = Character.toString(tempStr.charAt(i));
				str = tempStr.toUpperCase();
				System.out.print(str);
			}else{
				str = Character.toString(tempStr.charAt(i));
				str = str.toLowerCase();
				System.out.print(str);
			}
		}*/

		// output
		/*for (int i = 0; i < tempStr.length(); i++) {
			System.out.print(tempStr);
		}*/
		for(int i= 0; i < tempStr.length(); i++){
			if(Character.isLowerCase(tempStr.charAt(i)))
				System.out.print(Character.toUpperCase(tempStr.charAt(i)));
		else
			System.out.print(Character.toLowerCase(tempStr.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