import collections
N = int(input())
A = list(map(int, input().split()))
D = collections.deque(A)
aliceWin = False
while len(D) and D[0]==1:
    D.popleft()
    aliceWin = not aliceWin
if len(D)==0:
    if aliceWin:
        print('Alice')
    else:
        print('Bob')
    exit()

aliceWin = True 
while len(D) and D[-1]==1:
    D.pop()
    aliceWin = not aliceWin
if aliceWin:
    print('Alice')
else:
    print('Bob')