import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		
		Scanner sc = new Scanner(System.in);
		int A = Integer.parseInt(sc.next());
		int B = Integer.parseInt(sc.next());
		sc.close();
		
		if ((A == 1 && B == 2) || (B == 1 && A == 2) ) {
			
			System.out.print(3);
		}
		
		if ((A == 2 && B == 3) || (B == 2 && A == 3) ) {
			
			System.out.print(1);
		}

		if ((A == 1 && B == 3) || (B == 1 && A == 3) ) {
			
			System.out.print(2);
		}
		
	}

}
/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