import java.util.Scanner;
public class Main {
    public static void main(String[] args) {
        Scanner scan = new java.util.Scanner(System.in);
        String str = scan.nextLine();
        for(int i = 0; i < str.length(); i++){
            if(Character.isUpperCase(str.charAt(i))){
                System.out.print(Character.toLowerCase(str.charAt(i)));
            }else{
                System.out.print(Character.toUpperCase(str.charAt(i)));
            }
        }
        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