import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        try(Scanner cs = new Scanner(System.in)){
            String line = cs.nextLine();
            String answer = "";
            int length = line.length();
            for(int i =0;i<length;i++){
                char ch = line.charAt(i);
                if(Character.isLowerCase(ch)){
                    System.out.print(Character.toUpperCase(ch));
                }else{
                    System.out.print(Character.toLowerCase(ch));
                }
            }
            System.out.printf("\n");
        }
    }

}

/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