import java.util.*;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int alfa = 32;
		String line, ans; char[] lineC;
		
		ans = "";
		line = in.nextLine();
		lineC = line.toCharArray();
		
		for(int i=0;i<lineC.length;i++){
			if(Character.isUpperCase(lineC[i]))
				ans += (char)(lineC[i] + alfa);
			else if(Character.isLowerCase(lineC[i]))
				ans += (char)(lineC[i] - alfa);
			else ans += lineC[i];
		}
		
		System.out.println(ans);
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz