N, M = map(int, input().split())

if N%2 == 0:
	print(N*M)
	exit()
c = 0
ans = 0
for b in range(29, -1, -1):
	if M>>b&1:
		ans += (N-1) * (1<<b)
		if c < N: c += 1
	else:
		ans += (c//2 * 2) * (1<<b)
print(ans)