import java.util.*;
class No163{
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		
		String str = sc.next();
		char[] c = str.toCharArray();
		
		
		for(int i=0; i<c.length; i++){
			if((int)c[i]>=97 && (int)c[i]<=122){
				System.out.print(String.valueOf(c[i]).toUpperCase());
			}else{
				System.out.print(String.valueOf(c[i]).toLowerCase());
			}
		}
	}
}