import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();

		Map<String, Long> storage = new HashMap<String, Long>();
		System.out.println(calculateCutCount(n, m, storage));
	}

	public static long calculateCutCount(long n, long m, Map<String, Long> storage) {
		if (storage.containsKey(n + ":" + m)) {
			return storage.get(n + ":" + m);
		}
		if (n == 1)
			return m - 1;
		if (m == 1)
			return n - 1;

		long result = 0;
		if (n > m) {
			if (n % 2 == 0) {
				result = 1 + (2 * calculateCutCount(n / 2, m, storage));
			} else {
				result = 1 + calculateCutCount(n / 2, m, storage) + calculateCutCount(n / 2 + (n % 2), m, storage);
			}
		} else {
			if (m % 2 == 0) {
				result = 1 + (2 * calculateCutCount(n, m / 2, storage));
			} else {
				result = 1 + calculateCutCount(n, m / 2, storage) + calculateCutCount(n, m / 2 + (m % 2), storage);
			}
		}

		storage.put(n + ":" + m, result);
		return result;
	}
}