/* -*- coding: utf-8 -*-
 *
 * 3342.cc:  No.3342 AAB Game - yukicoder
 */

#include<cstdio>
#include<algorithm>

using namespace std;

/* constant */

const int MAX_N = 200000;

/* typedef */

/* global variables */

char s[MAX_N + 4];

/* subroutines */

/* main */

int main() {
  int n;
  scanf("%d%s", &n, s);

  int x = 0;
  for (int i = n - 1; i >= 0; i--)
    x = (x * 2 + (s[i] - 'A')) % 3;

  if (x % 3 != 0) puts("Alice");
  else puts("Bob");

  return 0;
}