package yukicoder;

import java.util.Scanner;

public class N163 {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String hoge = sc.nextLine();
		String fuga = "";
		Character c;
		for(int i = 0;i < hoge.length();++i){
			c = hoge.charAt(i);
			if(Character.isLowerCase(c)){
				c = Character.toUpperCase(c);
			}else{
				c = Character.toLowerCase(c);
			}
			fuga += c;
		}
		System.out.println(fuga);
	}
}