import java.io.*;

public class Main {
  public static void main(String[] args) {
    BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
    try {
      char[] str = reader.readLine().toCharArray();

      for (int i = 0; i < str.length; i++) {
        if (Character.isUpperCase(str[i])) {
          System.out.print(Character.toLowerCase(str[i]));
        }
        else if (Character.isLowerCase(str[i])) {
          System.out.print(Character.toUpperCase(str[i]));
        }
        else {
          System.out.print(str[i]);
        }
      }
      System.out.println();
    }
    catch (IOException e) {
      System.out.println(e);
    }
  }
}
/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