import java.io.*;
public class Main{
 public static void main(String[] args)throws IOException{
 BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
     String input=br.readLine();
     for(int i=0;i<input.length();i++){
         char a=input.charAt(i);
         if(Character.isUpperCase(a)){
           System.out.print(Character.toLowerCase(a));
         }else{
               System.out.print(Character.toUpperCase(a));
         }
     }
     System.out.print("\n");
 }
}
/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