import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        int A, B;
        Scanner scan = new Scanner(System.in);
        A = scan.nextInt();
        B = scan.nextInt();
        if(A==1&&B==2||A==2&B==1){
            System.out.println(3);
        }if(A==1&&B==3||A==3&B==1){
            System.out.println(2);
        }if(A==2&&B==3||A==3&B==2){
            System.out.println(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