import java.io.BufferedReader; import java.io.InputStreamReader; import java.math.BigInteger; public class Main { public static void main(String[] args) throws Exception { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); String[] sa = br.readLine().split(" "); br.close(); BigInteger ba = new BigInteger(sa[0]); BigInteger bb = new BigInteger(sa[1]); int ans = ba.add(bb).intValue(); System.out.println(ans == 5 ? 0 : ans); } }