#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); i++)
using namespace std;
using ll = long long;
using pii = pair<int, int>;

int main() {
  int n;
  cin >> n;
  int turn = 1; //0:alice 1:bob
  rep(i, n) {
    int a;
    cin >> a;
    if (i == 0) turn = !turn;
    else if (i < n - 1) {
      if (a == 1) turn = !turn;
    }
    else {
      if (a == 1) turn = !turn;
      else turn = 0;
    }
  }
  if (turn == 0) cout << "Alice" << endl;
  else cout << "Bob" << endl;
  return 0;
}