N,M = map(int, input().split())
ans1 = 1
for i in range(N-1):
    if pow(2,i+1)<=M:
        ans1+=pow(2,i+1)
    else:
        break
ans = M
while N>1 and M>=2:
    M = -(-M//2)
    ans += M
    N-=1
if M>=2:
    print(ans1)
else:
    print(ans+N-1)