import java.io.*;
class Main
{
    public static void main(String args[])throws IOException
    {
	BufferedReader input=new BufferedReader(new InputStreamReader(System.in));
	String str=input.readLine();
	for(int i=0;i<str.length();i++)
	    {
		char b=str.charAt(i);
			
		if(('a'<=b) && (b<='z'))
			    System.out.print(Character.toUpperCase(b));
			
		else if(('A'<=b) && (b<='Z'))
			    System.out.print(Character.toLowerCase(b));
		else System.out.print(b);	
			    

		    
		
	    }
	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