#include <bits/stdc++.h>

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
const int N = 2000010, MOD = 1e9 + 7, INF = 0x3f3f3f3f;
int n, m, w[N];

char s[N];

int main() {
    cin >> n;
    scanf("%s", s + 1);
    int v = 0;
    for (int i = 1; i < n + 1; i++) v += (s[i] == 'B') * (1 + (i & 1 ^ 1));
    puts(v % 3 ? "Alice" : "Bob");
    return 0;
}