import java.util.*;

public class Main {
    private static final Scanner scn = new Scanner(System.in);
    
    public static void main(String[] args) {
        char[] ary = scn.nextLine().toCharArray();
        StringBuilder sb = new StringBuilder();
        for(char elm : ary) {
            if(Character.isLowerCase(elm)) {
                 sb.append(Character.toUpperCase(elm));
            } else {
                 sb.append(Character.toLowerCase(elm));
            }
        }
        System.out.println(sb);
    }
}
/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