import java.util.Scanner;
public class No0163 {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String falsePass = sc.nextLine();
		String truePass = new String();
		for(int i=0; i<falsePass.length(); i++){
			char c = falsePass.charAt(i);
			if((int) c >= 'A' && (int) c <= 'Z'){
				truePass += String.valueOf(c).toLowerCase();
			}else{
				truePass += String.valueOf(c).toUpperCase();
			}
		}
		System.out.println(truePass);
	}
}