import java.io.*;

class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String s=br.readLine();
        for(int i=0;i<s.length();i++){
        	if(Character.isUpperCase(s.charAt(i))){
            	System.out.print(s.substring(i,i+1).toLowerCase());
        	}else{
        		System.out.print(s.substring(i,i+1).toUpperCase());
        	}
        }
        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