import sys
import math
from math import sin, cos, tan
from functools import reduce
from collections import deque
import heapq
sys.setrecursionlimit(1000000)
intm1 = lambda x:int(x)-1

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

dp = [[True, False] for _ in range(N + 1)] # True if Alice win
for i in range(N - 1, -1, -1):
	if A[i] == 1:
		dp[i][0] = not dp[i + 1][0]
		dp[i][1] = not dp[i + 1][1]
	else:
		dp[i][0] = True
		dp[i][1] = False
print('Alice' if dp[0][0] else 'Bob')