import java.util.Scanner;

public class Main{
  public static void main(String[]args){
      try(Scanner sc = new Scanner(System.in)){
        String line = sc.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.printf("%s", Character.toUpperCase(ch));
          }else{
              System.out.printf("%s", Character.toLowerCase(ch));
          }
        }
        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