import java.util.*;
import java.lang.*;



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 if(Character.isLowerCase(str.charAt(i))){
            System.out.print(Character.toUpperCase(str.charAt(i)));
         }else{

         System.out.print(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