#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 5;
int n, g_n;
int prime[N], tot;
int g_prime[N], cnt;
bool flag[N];
vector<pair<int, int> > g;
int L[N], R[N], id[N];
inline int min(int a, int b) { return a > b ? b : a; }
inline void pre() {
  for (register int i = 2; i <= n; ++i) {
    if (!flag[i]) {
      prime[++tot] = i;
    }
    for (register int j = 1; j <= tot; ++j) {
      if (i * prime[j] > n) break;
      flag[i * prime[j]] = 1;
      if (i % prime[j] == 0) break;
    }
  }
}
inline void get_pig(int pos) {
  for (register int i = L[pos]; i <= R[pos]; ++i) {
    int tot;
    cout << "A " << g_prime[i] << endl;
    cin >> tot;
    if (tot) {
      g.push_back(make_pair(g_prime[i], 1));
      return;
    }
  }
}
int main() {
  scanf("%d", &n);
  if (n == 1) {
    puts("C 1");
    fflush(stdout);
    return 0;
  }
  pre();
  g_n = sqrt(n);
  for (register int i = 1; i <= tot; ++i) {
    if (prime[i] <= g_n)
      g_prime[++cnt] = prime[i];
    else
      break;
  }
  for (register int i = 1; i <= cnt; ++i) {
    int x = g_prime[i];
    cout << "B " << x << endl;
    int cnt;
    cin >> cnt;
    cout << "A " << x << endl;
    cin >> cnt;
    int k = 0, res = x;
    if (cnt) {
      while (cnt) {
        ++k;
        res *= x;
        if (res > n) break;
        cout << "A " << res << endl;
        cin >> cnt;
      }
      g.push_back(make_pair(x, k));
    }
  }
  for (register int i = cnt + 1; i <= tot; ++i) {
    g_prime[++prime[0]] = prime[i];
  }
  cnt = prime[0];
  int size = sqrt(cnt);
  int sum_g = 0;
  if (cnt % size)
    sum_g = cnt / size + 1;
  else
    sum_g = cnt / size;
  for (register int i = 1; i <= sum_g; ++i) {
    L[i] = (i - 1) * size + 1;
    R[i] = min(i * size, cnt);
  }
  for (register int i = 1; i <= sum_g; ++i)
    for (register int j = L[i]; j <= R[i]; ++j) id[j] = i;
  cout << "A 1" << endl;
  cin >> cnt;
  for (register int k = 1; k <= sum_g; ++k) {
    int expect = 0;
    for (register int i = L[k]; i <= R[k]; ++i) {
      int x;
      cout << "B " << g_prime[i] << endl;
      cin >> x;
      expect += x;
    }
    int tot;
    cout << "A 1" << endl;
    cin >> tot;
    if (cnt - tot != expect) {
      get_pig(k);
      break;
    }
    cnt = tot;
  }
  int ans = 1;
  int sx = g.size();
  for (register int k = 0; k < sx; ++k) {
    int x = g[k].first, p = g[k].second;
    while (p) {
      ans *= x;
      --p;
    }
  }
  cout << "C " << ans << endl;
  return 0;
}
