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


public class Main {

	public static void main(String[] args) throws IOException{
		// 入力導入部
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		
		
		String strin=br.readLine();
		String[] str=strin.split("");
		
		
		
		for(int i=0;i<str.length;i++){
			if(str[i].equals(str[i].toLowerCase())){
				System.out.print(str[i].toUpperCase());
			}else System.out.print(str[i].toLowerCase());
		}br.close();
		System.out.println();
		}}
/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