import java.util.Scanner;

public class Main {

    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        for(char c : str.toCharArray()){
            if(65 <= c && c <= 90) System.out.print((char)(c + 32));
            else if(97 <= c && c <= 122) System.out.print((char)(c - 32));
            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