#include <bits/stdc++.h>
using namespace std;
const long long int MOD = 1e9 + 7;
vector<bool> isPrime;
void sieve(long long int n) {
  for (long long int i = 2; i <= n; i++) {
    if (isPrime[i]) {
      for (long long int j = 2 * i; j <= n; j += i) {
        isPrime[j] = false;
      }
    }
  }
}
void solve() {
  long long int n;
  cin >> n;
  isPrime.resize(n + 1, true);
  sieve(n);
  set<long long int> s;
  for (long long int i = 1; i <= n; i++) {
    s.insert(i);
  }
  long long int got;
  for (long long int i = 2; i * i <= n; i++) {
    if (!isPrime[i]) continue;
    cout << "B " << i << endl;
    for (long long int j = i; j <= n; j += i) {
      s.erase(j);
    }
    cin >> got;
  }
  cout << "A " << 1 << endl;
  cin >> got;
  if ((int)s.size() == got) {
    long long int ans = 1;
    vector<long long int> bag[100];
    long long int srt = sqrt(n);
    long long int c = 0;
    for (long long int i = srt + 1; i <= n; i++) {
      if (!isPrime[i]) continue;
      bag[c / 100].push_back(i);
      c++;
    }
    for (long long int i = 0; i <= c / 100; i++) {
      for (auto it : bag[i]) {
        cout << "B " << it << endl;
        cin >> got;
        s.erase(it);
      }
      cout << "A " << 1 << endl;
      cin >> got;
      if (got != (int)s.size()) {
        for (auto it : bag[i]) {
          cout << "A " << it << endl;
          cin >> got;
          if (got) ans *= it;
        }
        break;
      }
    }
    cout << "C " << ans << endl;
  } else {
    long long int ans = 1;
    for (long long int i = 2; i * i <= n; i++) {
      if (!isPrime[i]) continue;
      long long int val = i;
      while (val <= n) {
        cout << "A " << val << endl;
        cin >> got;
        if (got == 0) {
          val /= i;
          ans *= val;
          break;
        } else {
          val *= i;
          if (val > n) ans *= (val / i);
        }
      }
    }
    for (long long int i = sqrt(n) + 1; i <= n; i++) {
      if (!isPrime[i]) continue;
      cout << "B " << i << endl;
      cin >> got;
      if (got > 1) {
        ans *= i;
      }
    }
    cout << "C " << ans << endl;
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  solve();
  return 0;
}
