N, X, Y = map(int, input().split())

if Y%2 == 0:
    if X == Y:
        print(0)
    else:
        print(-1)
    exit()

ans = [N]
pre = -1
for i in reversed(range(N)):
    if 1<<i & Y:
        if pre == -1:
            pre = i
        else:
            ans.append(pre-i)
            pre = i

print(len(ans))
print(*ans)