#include "bits/stdc++.h"

using namespace std;
using ll = long long;

void Main() {
    int N;
    cin >> N;
    int A;
    cin >> A;
    int WA = 1;
    int WB = 0;
    for (int i = 1; i < N; ++i) {
        int a;
        cin >> a;
        if (a == 1) {
            swap(WA, WB);
        }
        else {
            int max_ = max(WA, WB);
            int min_ = min(WA, WB);
            WA = max_;
            WB = min_;
        }
    }
    cout << (WA == 1 ? "Alice" : "Bob") << endl;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    std::cout << std::fixed << std::setprecision(15);
    Main();
    return 0;
}