#include <bits/stdc++.h>
using namespace std;
namespace IO {
char buf[1 << 23], *p1 = buf, *p2 = buf, obuf[1 << 23], *O = obuf;
inline int read() {
  int x = 0, sign = 0;
  char s =
      (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
           ? EOF
           : *p1++);
  while (!isdigit(s))
    sign |= s == '-',
        s = (p1 == p2 &&
                     (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
                 ? EOF
                 : *p1++);
  while (isdigit(s))
    x = (x << 1) + (x << 3) + (s - '0'),
    s = (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 22, stdin), p1 == p2)
             ? EOF
             : *p1++);
  return sign ? -x : x;
}
inline void print(int x) {
  if (x > 9) print(x / 10);
  (*O++ = x % 10 + '0');
}
}  // namespace IO
namespace math {
const int mod = 1e9 + 7;
const int maxn = 1e6 + 5;
long long ksm(long long a, long long b) {
  long long s = 1, m = a;
  while (b) {
    if (b & 1) s = s * m % mod;
    m = m * m % mod, b >>= 1;
  }
  return s;
}
long long inv(long long x) { return ksm(x, mod - 2); }
long long fc[maxn], ifc[maxn];
void init_m(int n) {
  fc[0] = 1;
  for (int i = 1; i <= n; i++) fc[i] = fc[i - 1] * i % mod;
  ifc[n] = inv(fc[n]);
  for (int i = n - 1; i >= 0; i--) ifc[i] = ifc[i + 1] * (i + 1) % mod;
}
long long C(long long n, long long m) {
  return fc[n] * ifc[m] % mod * ifc[n - m] % mod;
}
}  // namespace math
using namespace IO;
const int N = 1e5 + 5;
int n, p[N], pre[N], cnt, pr[N], res, pd[N];
int gt, qu, ori;
void del(int x) {
  for (int j = x; j <= ori; j += x)
    if (!pd[j]) res--, pd[j] = 1;
}
void pa(int x) {
  qu++;
  assert(qu < 1e4);
  cout << "A " << x << endl;
  cin >> gt;
}
void emplace_back(int x) {
  qu++;
  assert(qu < 1e4 && x > 1);
  cout << "B " << x << endl;
  cin >> gt;
}
int find(int st) {
  if (st == 0) return 1;
  int lim = st / 2;
  for (int i = st; i > lim; i--) emplace_back(pr[i]), del(pr[i]);
  pa(1);
  if (gt != res) {
    int ans = 1;
    for (int i = st; i > lim; i--) {
      long long tmp = pr[i];
      while (tmp <= n) {
        pa(tmp);
        if (!gt) {
          tmp /= pr[i];
          break;
        }
        tmp *= pr[i];
      }
      if (tmp > n) tmp /= pr[i];
      if (tmp > 1) ans *= tmp, n /= tmp;
    }
    return ans * find(min(lim, pre[n]));
  } else
    return find(lim);
}
void solve() {
  cin >> n, res = ori = n;
  int cal = 0;
  for (int i = 2; i <= n; i++) {
    if (!p[i]) {
      pr[++cnt] = i;
      for (int j = i + i; j <= n; j += i) p[j] = 1;
    }
    pre[i] = pre[i - 1] + !p[i];
  }
  cout << "C " << find(cnt) << endl, assert(qu < 1e4);
}
int main() {
  int t = 1;
  while (t--) solve();
  return 0;
}
