import java.io.*;

class Main{
	public static void main(String[] args)throws IOException{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String str = br.readLine();
		char[] cr = str.toCharArray();
		for(int i=0;i<cr.length;i++){
			if(Character.isLowerCase(cr[i])){
				System.out.print(Character.toUpperCase(cr[i]));
			}else{
				System.out.print(Character.toLowerCase(cr[i]));
			}
		}
		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