#include<bits/stdc++.h>
using namespace std;

int main() {
    int n;
    cin >> n;
    vector<int> a(n + 1);
    for (int i = 1; i <= n; i++) cin >> a[i];
    vector<int> dp(n + 1, 2);
    for (int i = 1; i <= n; i++) {
        if (a[i] == 1) dp[i] = 3 - dp[i - 1];
        else dp[i] = 1;
    }
    if (dp[n] == 1) cout << "Alice" << endl;
    else cout << "Bob" << endl;
}