n = int(input())
a = list(map(int, input().split()))
a = a[::-1]  # Reverse the array

count = 0
for x in a:
    if x == 1:
        count += 1
    else:
        break

if all(x == 1 for x in a):
    print("Alice" if count % 2 == 1 else "Bob")
else:
    print("Alice" if count % 2 == 0 else "Bob")