#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair<ll,ll> P;
typedef vector<ll> VI;
typedef vector<VI> VVI;
#define REP(i,n) for(ll i=0;i<(n);i++)
#define ALL(v) v.begin(),v.end()
constexpr ll MOD=1000000007;
constexpr ll INF=2e18;

int main(){
    int n; cin >> n;
    VI a(n); REP(i,n) cin >> a[i];
    bool f=(n+1)%2;
    REP(i,n){
        if(a[n-1-i]!=1){
            f=i%2;
            break;
        }
    }
    if(!f)
        cout << "Alice" << endl;
    else
        cout << "Bob" << endl;
}