#include <bits/stdc++.h>
using namespace std;
const long long inf = 1e9 + 7;
const long long linf = 1e18 + 1;
template <typename T>
class V : public vector<T> {
 public:
  V(long long sz = 0, T init = T()) : vector<T>(sz, init) {}
};
template <typename T = long long>
T nxt() {
  T x;
  cin >> x;
  return x;
}
template <typename T = long long>
void read(vector<T> &x) {
  for (T &i : x) cin >> i;
}
template <typename T = long long>
void read(V<T> &x) {
  for (T &i : x) cin >> i;
}
template <typename T = long long>
void print(vector<T> &x) {
  for (T v : x) {
    cout << v << " ";
  }
}
template <typename T = long long>
void print(V<T> &x) {
  for (T v : x) {
    cout << v << " ";
  }
}
template <typename T = long long>
void printset(set<T> &x) {
  for (auto v : x) cout << v << " ";
  cout << endl;
}
signed main() {
  ;
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  long long n = nxt();
  vector<long long> erat(n + 1, 0);
  vector<long long> prime;
  for (long long i = 2; i <= n; ++i) {
    if (!erat[i]) {
      prime.push_back(i);
      for (long long j = 2 * i; j <= n; j += i) {
        erat[j] = 1;
      }
    }
  }
  long long j = 0;
  vector<long long> ans;
  long long op_count = 0;
  for (; j < prime.size() && prime[j] * prime[j] <= n; ++j) {
    cout << "B " << prime[j] << endl;
    cout.flush();
    long long res;
    cin >> res;
    cout << "A " << prime[j] << endl;
    cin >> res;
    if (res) {
      ans.push_back(prime[j]);
    }
    op_count += 2;
  }
  while (j < prime.size()) {
    long long right = min(j + 100, (long long)prime.size());
    cout << "A " << 1 << endl;
    cout.flush();
    long long cnt;
    cin >> cnt;
    long long sum = 0;
    op_count++;
    for (long long i = j; i < right; ++i) {
      long long v = prime[i];
      cout << "B " << v << endl;
      cout.flush();
      long long res;
      cin >> res;
      op_count++;
      sum += res;
    }
    cout << "A " << 1 << endl;
    op_count++;
    cout.flush();
    long long cnt2;
    cin >> cnt2;
    if (cnt2 + sum != cnt) {
      for (long long i = j; i < right; ++i) {
        cout << "A " << prime[i] << endl;
        op_count++;
        cout.flush();
        long long res;
        cin >> res;
        if (res) {
          ans.push_back(prime[i]);
          break;
        }
      }
      break;
    }
    j = right;
  }
  long long x = 1;
  assert(op_count < 9900);
  for (long long v : ans) {
    long long prom = v;
    while (prom <= n) {
      long long nxt_prom = prom * v;
      if (nxt_prom > n) break;
      cout << "A " << nxt_prom << endl;
      op_count++;
      cout.flush();
      long long res;
      cin >> res;
      if (res == -1)
        assert(0);
      else if (res > 0) {
        prom = nxt_prom;
      } else {
        break;
      }
    }
    x *= prom;
  }
  cout << "C " << x << endl;
  return 0;
}
