int main()
{
int n, nn = 0;
cin >> n;
int a[100001], b[100001];
for (int i = 0; i < n; ++i)
{
cin >> b[i];
if (i == 0 || b[i] != b[i - 1])
a[nn++] = b[i];
}
int ans = 0;
if (a[0] == 1)
ans = nn;
else
ans = nn - 1;
if (ans % 2)
cout << "Alice" << endl;
else
cout << "Bob" << endl;
return 0;
}