import java.util.Scanner;

public class Main{
    public static void main(String[] args){
	Scanner sc = new Scanner(System.in);
	int A = sc.nextInt();
	int B = sc.nextInt();
	if((A==1 && B==2)||(A==2 && B==1)) System.out.print(3);
	else if((A==1 && B==3)||(A==3 && B==1)) System.out.print(2);
	else System.out.print(1);
    }
}

/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