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

if N==1:
    print(M)
    exit()

a = M
ans=a
for i in range(N-1):
    if a==0:
        break
    elif a%2==0:
        a//=2
        ans+=a
    else:
        a = a//2+1
        ans+=a

print(ans)