import sys

sys.setrecursionlimit(10**7)
def I(): return int(sys.stdin.readline().rstrip())
def MI(): return map(int,sys.stdin.readline().rstrip().split())
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
def LI2(): return list(map(int,sys.stdin.readline().rstrip()))
def S(): return sys.stdin.readline().rstrip()
def LS(): return list(sys.stdin.readline().rstrip().split())
def LS2(): return list(sys.stdin.readline().rstrip())


N = I()
A = LI()

count = 0
for i in range(N-1,-1,-1):
    if A[i] == 1:
        count += 1
    else:
        break

if count == N:
    if N % 2 == 1:
        print('Alice')
    else:
        print('Bob')
else:
    if count % 2 == 0:
        print('Alice')
    else:
        print('Bob')