import java.util.Scanner;

public class Main {
	public static void main(String[] args)
	{
		Scanner scan = new Scanner(System.in);
		scan.useDelimiter("\\n");
		String str = scan.next();
		char[] ans = str.toCharArray();
		
		for(int i = 0;i < ans.length;i++)
		{
			if(Character.isLowerCase(ans[i]))
			{
				ans[i] = Character.toUpperCase(ans[i]);
			}else if(Character.isUpperCase(ans[i])){
				ans[i] = Character.toLowerCase(ans[i]);
			}
		}
		
		for(int i = 0;i < ans.length;i++)
		{
			System.out.print(ans[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