#include <bits/stdc++.h>
using namespace std;
int main(){
  int N;
  cin >> N;
  vector<int> A(N);
  for (int i = 0; i < N; i++){
    cin >> A[i];
  }
  int p = -1;
  for (int i = 1; i < N; i++){
    if (A[i] == 1){
      p = i;
      break;
    }
  }
  if (p == -1){
    cout << "Alice" << endl;
  } else if ((N - p) % 2 == 0){
    cout << "Alice" << endl;
  } else {
    bool ok = true;
    for (int i = p + 2; i < N; i++){
      if (A[i] > 1){
        ok = false;
      }
    }
    if (!ok){
      cout << "Alice" << endl;
    } else {
      cout << "Bob" << endl;
    }
  }
}