import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int[] a = new int[n];
		for (int i = 0; i < n; i++) {
			a[i] = sc.nextInt();
		}
		sc.close();

		boolean[] b = new boolean[n + 1];
		for (int i = 0; i < n; i++) {
			b[i + 1] = !b[i];
			if (!b[i + 1] && a[i] > 1) {
				b[i + 1] = !b[i + 1];
			}
		}
		if (b[n]) {
			System.out.println("Alice");
		} else {
			System.out.println("Bob");
		}
	}
}