import java.util.Scanner;

public class Main{
	public static void main(String [] args){
		Scanner sc = new Scanner(System.in);
		String input = sc.nextLine();
		String work = "";
		for(int i = 0; i < input.length(); i++){
			work = input.substring(i,i+1);
			if(Character.isUpperCase(work.charAt(0))){
				System.out.print(work.toLowerCase());
			}else{
				System.out.print(work.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