import java.io.*;
public class Main {
	void run(){
		InputStreamReader is = new InputStreamReader(System.in);
		BufferedReader br = new BufferedReader(is);
		String str = "";
		try{
		str = br.readLine();
		}catch(IOException e){
			System.out.println(e);
		}
		char c[] = str.toCharArray();
		for(int i = 0;i < c.length;i++){
			if(Character.isUpperCase(c[i])){
				c[i] = Character.toLowerCase(c[i]);
			}else if(Character.isLowerCase(c[i])){
				c[i] = Character.toUpperCase(c[i]);
			}
			System.out.print(c[i]);
		}
		System.out.println("");
	}
	public static void main(String args[]){
		Main m = new Main();
		m.run();
	}
}
/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