import java.util.Scanner;

class Main {

	public static void main(String[] args) {

	char[] inputline;
	Scanner stdIn = new Scanner(System.in);

	inputline =  stdIn.nextLine().toCharArray();

	for(int i = 0; i < inputline.length; i++) {
		if(Character.isLowerCase(inputline[i])) {
			inputline[i] = Character.toUpperCase(inputline[i]);
		} else {
			inputline[i] = Character.toLowerCase(inputline[i]);
		}
	}

	System.out.println(inputline);

	stdIn.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