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#include <bits/stdc++.h>
using namespace std;
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define vi vector<int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10), cin.tie(0), cout.tie(0);
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define trav(a, x) for (auto &a : x)
#define all(c) (c).begin(), (c).end()
#define sz(X) (int)((X).size())
typedef long double ld;
typedef unsigned long long ull;
typedef long long ll;
#ifdef LOCAL
ostream &operator<<(ostream &out, string str) {
   for (char c : str)
      out << c;
   return out;
}
template <class L, class R> ostream &operator<<(ostream &out, pair<L, R> p) { return out << "(" << p.st << ", " << p.nd << ")"; }
template <class L, class R, class S> ostream &operator<<(ostream &out, tuple<L, R, S> p) {
   auto &[a, b, c] = p;
   return out << "(" << a << ", " << b << ", " << c << ")";
}
template <class T> auto operator<<(ostream &out, T a) -> decltype(a.begin(), out) {
   out << '{';
   for (auto it = a.begin(); it != a.end(); it = next(it))
      out << (it != a.begin() ? ", " : "") << *it;
   return out << '}';
}
void dump() { cerr << "\n"; }
template <class T, class... Ts> void dump(T a, Ts... x) {
   cerr << a << ", ";
   dump(x...);
}
#define debug(...) cerr << "[" #__VA_ARGS__ "]: ", dump(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define int long long
const int BASE = 9;

namespace EXP {

   typedef __int128_t lll;
   const int MAXN = 1e18; // pow(9, 4) + 22;
   set<int> S1;

   void pre() {
      for (lll i = 1; i < MAXN; i *= 2)
         for (lll j = i; j < MAXN; j *= 3)
            for (lll k = j; k < MAXN; k *= 5)
               for (lll l = k; l < MAXN; l *= 7)
                  S1.insert(l);
      debug(S1);
   }
   pair<int, vector<int>> get(int n) {
      auto itr = S1.upper_bound(n);
      auto x = *(--itr);
      auto rest = n - x;
      assert(x <= n);
      debug(x);
      vector<int> res;
      for (int t = 9; t > 1; t--)
         while (x % t == 0) {
            x /= t;
            res.push_back(t);
         }
      assert(x == 1);
      return {rest, res};
   }

   string multiply_experimental(string s, int t) {
      if (t == 0)
         return "";
      auto [rest, X] = get(t);

      string res = "";
      for (auto x : X)
         res += to_string(x) + "[";
      res += s;
      rep(i, sz(X)) res += "]";
      debug(t, X, sz(X));

      return res + multiply_experimental(s, rest);
   }

} // namespace EXP

string multiply_small(string s, int t) {
   assert(t <= BASE && t >= 0);
   if (t == 0)
      return "";
   if (t == 1)
      return s;

   if (sz(s) == 1)
      return to_string(t) + s;
   else
      return to_string(t) + "[" + s + "]";
}

string multiply_normal(string s, int t) {
   assert(t >= 0);
   if (t == 0)
      return "";

   int rest = t / BASE;
   auto x = t % BASE;
   return multiply_normal(multiply_small(s, BASE), rest) + multiply_small(s, x);
}

string multiply(string s, int t) {
   auto s1 = multiply_normal(s, t);
   auto s2 = EXP::multiply_experimental(s, t);
   return sz(s1) > sz(s2) ? s2 : s1;
}

string draw_triangle(int n);

string draw_traingle_BL_filled(int n) {
   if (n == 0)
      return "";
   if (n == 1)
      return "B";
   auto S1 = multiply("BD", n - 1);
   auto S2 = multiply("BF", n - 1);
   auto S3 = draw_triangle(n - 2);
   return S1 + S2 + S3 + "B";
}

////////////////////////////////// NORMAL TRIANGLES

string make_n_even(int n) {
   auto S1 = multiply("D", n);
   auto S2 = multiply("FB", n - 1);
   debug("ME", n, sz(S1), sz(S2));
   return S1 + S2 + "F";
}

string draw_triangle(int n) {
   debug("DT", n);
   if (n == 0)
      return "";
   if (n & 1) {
      auto S1 = make_n_even(n);
      auto S2 = draw_triangle(n - 1);
      return S1 + S2 + "B";
   }
   int t = n / 2;

   auto S1 = multiply("D", n);

   auto zyg = multiply("FB", t);
   auto bck = multiply("D", t);
   auto S2 = multiply(zyg + "F" + bck, t);

   auto S3 = multiply("F", t);

   auto TR = draw_traingle_BL_filled(t);
   auto S4 = multiply(TR, 2);

   debug(t, sz(S1), sz(S2), sz(S3), sz(S4));

   return S1 + S2 + S3 + S4;
}
////////////////////////////////////

int32_t main() {
   _upgrade;
   EXP::pre();

   int n;
   cin >> n;

   auto S = draw_triangle(n);
   debug(sz(S));
   cout << S << endl;
}