import java.util.*;
import java.io.*;
import static java.lang.System.*;
import static java.lang.Math.*;

public class Main {
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    String str = sc.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