use std::collections::VecDeque;

const INF: usize = 1usize << 60;

fn dfs(i: usize, j: usize, a: &Vec<usize>, dp: &mut Vec<Vec<usize>>) -> usize {
    if dp[i][j] < INF { return dp[i][j]; }
    if j == 0 {
        dp[i][j] = 1 - dfs(i-1, a[i-1], a, dp);
    } else {
        let left = dfs(i, 0, a, dp);
        let right = dfs(i-1, a[i-1], a, dp);
        if left == right {
            dp[i][j] = 1 - left;
        } else {
            dp[i][j] = 0;
        }
    }
    dp[i][j]
}

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 a = a.into_iter().map(|v| if v == 1 { 0usize } else { 1usize }).collect::<Vec<_>>();
    let mut dp = vec![vec![INF; 2]; n];
    dp[0][0] = 0;
    dp[0][1] = 0;
    let mut deque = VecDeque::new();
    deque.push_back((0, a[0]));
    dfs(n-1, a[n-1], &a, &mut dp);
    if dp[n-1][a[n-1]] == 0 {
        println!("Alice");
    } else {
        println!("Bob");
    }
}