const INF: usize = 1usize << 60;

fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();
    let mut a = String::new();
    std::io::stdin().read_line(&mut a).ok();
    let a: Vec<usize> = a.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();

    let mut dp = vec![vec![INF; 2]; n+1];
    dp[0][0] = 0;
    dp[0][1] = 0;
    for i in 0..n {
        if a[i] == 1 {
            dp[i+1][0] = 1 - dp[i][1];
            dp[i+1][1] = 1 - dp[i][1];
        } else {
            dp[i+1][0] = 1 - dp[i][1];
            dp[i+1][1] = 1;
        }
    }
    if dp[n][1] == 0 {
        println!("Bob");
    } else {
        println!("Alice");
    }
}