import java.util.Scanner;

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

		Scanner scan = new Scanner(System.in);

		String str = scan.nextLine();
		
		char[] c = str.toCharArray();
		
		for(int i=0; i<c.length; i++)
		{
			c[i] = Character.isUpperCase(c[i]) ? Character.toLowerCase(c[i]) : Character.isLowerCase(c[i]) ? Character.toUpperCase(c[i]) : c[i];
		}
		
		System.out.println(c);
		scan.close();
	}
}
/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