package ALGO_84;

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
	Scanner scanner=new Scanner(System.in	);
	String a=scanner.nextLine();
    char[] b = a.toCharArray();
    for(int i=0;i<b.length;i++){
    	char ch = b[i];
    	if(Character.isUpperCase(ch)){
    		 b[i]=Character.toLowerCase(ch);
    	}else if(Character.isLowerCase(ch)){
    		 b[i]=Character.toUpperCase(ch);
    	}
    	System.out.print(b[i]);
    }
 
	}
}