import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class No00000163_Main {

	public static void main(String[] args) throws IOException {

		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		char[] charArr = br.readLine().toCharArray();
		char[] newCharArr = new char[charArr.length];
		for(int i = 0; i < charArr.length; i++) {
			if(Character.isUpperCase(charArr[i])) {
				newCharArr[i] = (char) (charArr[i] + 32);
			} else {
				newCharArr[i] = (char) (charArr[i] - 32);
			}
		}
		System.out.println(new String(newCharArr));
	}
}