import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Main {
	
	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);

		String input = sc.nextLine();
		
		for(char c : input.toCharArray()){
			System.out.print(('a' <= c && c <= 'z' || 'A' <= c && c <= 'Z') ? (char) (c ^ ('a' - 'A'))  : 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