import java.util.Scanner;

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

        String input = stdIn.nextLine();

        for(char c : input.toCharArray()) {
            if('A' <= c && c <= 'Z') {
                System.out.print((char)(c + 'a' - 'A'));
            } else if('a' <= c && c <= 'z') {
                System.out.print((char)(c + 'A' - 'a'));
            } else {
                System.out.print(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