import java.util.*;

public class Main {
    public static void main( String args[] ) {
        Scanner scan = new Scanner( System.in );
        char[] charaArray = scan.nextLine().toCharArray();
        scan.close();
        
        for( char chara: charaArray ) {
            char result;
            if( Character.isUpperCase(chara) ) {
                result = Character.toLowerCase(chara);
                
            } else {
                result = Character.toUpperCase(chara);
                
            }
            System.out.print( String.valueOf( result ) );
            
        }
        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