#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
using ll = long long;
using ull = unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)


int main(){
  string ansbuf[2] = {"Alice\n","Bob\n"};
  int N; cin >> N;
  vector<int> A(N); rep(i,N) cin >> A[i];
  while(A.size()){
    if(A.back() >= 2){ cout << ansbuf[0]; return 0; }
    A.pop_back();
    swap(ansbuf[0],ansbuf[1]);
  }
  cout << ansbuf[1];
  return 0;
}


struct ios_do_not_sync{
  ios_do_not_sync(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
  }
} ios_do_not_sync_instance;