#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define ALL(v) v.begin(), v.end()
typedef long long ll;

#include <bits/stdc++.h>
using namespace std;

int main(){
  ll n;
  cin>>n;
  vector<ll> A(n);
  rep(i,n) cin>>A[i];
  
  if(n==1){
    cout<<"Alice"<<endl;
    return 0;
  }
  
  int cnt=0;
  for(int i=n-1;i>=0;i--){
    if(A[i]==1) cnt++;
    else break;
  }
  
  if(cnt==n){
    if(cnt%2==0) cout<<"Bob"<<endl;
    else cout<<"Alice"<<endl;
    return 0;
  }
  
  if(cnt%2==1) cout<<"Bob"<<endl;
  else cout<<"Alice"<<endl;
  
  return 0;
}