import java.util.Scanner;

public class Main{

	static Scanner s=new Scanner(System.in);

	public static void main(String __[]){
		input();
		solve();
	}

	private static void input(){
	}

	private static void solve(){
		char c[] = s.nextLine().toCharArray();
		for(int i=0;i<c.length;i++)
			c[i]=c[i]<='Z'
			?Character.toLowerCase(c[i])
			:Character.toUpperCase(c[i]);
		System.out.println(String.valueOf(c));
	}
}
/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