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#include <cstdio>
#include <vector>
#include <string>
#include <unordered_map>
using namespace std;

typedef long long lol;
typedef pair<int, int> pii;
struct Key {
	int first;
	lol second;
	Key(int a, lol b) : first(a), second(b) {}
	bool operator==(const Key &oth) const {
		return first == oth.first && second == oth.second;
	}
};

template <> struct std::hash<Key> {
	std::size_t operator()(const Key &key) const {
		return (hash<int>()(key.first)) ^ (hash<lol>()(key.second));
	}
};

unordered_map<Key, pii> mem;

int minMulti(int len, lol n) {
	if (0 == n) return 0;
	if (1 == n) return len;
	if (n <= 9) {
		if (1 == len) return 2;
		if (2 == len && 2 == n) return 4;
		return len + 3;
	}
	Key key(len, n);
	if (mem.count(key) > 0) return mem[key].first;
	int res = 987654321;
	int b = 0;
	for (int mn=2; mn<=9; ++mn) {
		int cur = 3 + minMulti(len, n / mn) + minMulti(len, n % mn);
		if (cur < res) {
			res = cur;
			b = mn;
		}
	}
	mem[key] = { res, b };
	return res;
}

int apply(lol n, const char *s, int sz, char *buf) {
	if (0 == n) return 0;
	if (1 == n) {
		for (int i=0; i<sz; ++i)
			buf[i] = s[i];
		return sz;
	}
	if (n <= 9) {
		if (1 == sz) {
			buf[0] = "0123456789"[n];
			buf[1] = s[0];
			return 2;
		}
		if (2 == sz && 2 == n) {
			buf[0] = s[0];
			buf[1] = s[1];
			buf[2] = s[0];
			buf[3] = s[1];
			return 4;
		}
		buf[0] = "0123456789"[n];
		buf[1] = '[';
		for (int i=0; i<sz; ++i)
			buf[2 + i] = s[i];
		buf[sz + 2] = ']';
		return 3 + sz;
	}
	Key key(sz, n);
	int cnt = minMulti(sz, n);
	int mn = mem[key].second;
	int pos = apply(n % mn, s, sz, buf);
	buf[pos + 0] = "0123456789"[mn];
	buf[pos + 1] = '[';
	pos += 2;
	pos += apply(n / mn, s, sz, buf + pos);
	buf[pos++] = ']';
	return pos;
}

int apply(lol n, const string &s, char *buf) {
	if (0 == n) return 0;
	if (1 == n) {
		for (int i=0; i<s.size(); ++i)
			buf[i] = s[i];
		return s.size();
	}
	if (n <= 9) {
		if (1 == s.size()) {
			buf[0] = "0123456789"[n];
			buf[1] = s[0];
			return 2;
		}
		if (2 == s.size() && 2 == n) {
			buf[0] = s[0];
			buf[1] = s[1];
			buf[2] = s[0];
			buf[3] = s[1];
			return 4;
		}
		buf[0] = "0123456789"[n];
		buf[1] = '[';
		for (int i=0; i<s.size(); ++i)
			buf[2 + i] = s[i];
		buf[s.size() + 2] = ']';
		return 3 + s.size();
	}
	int sz = s.size();
	Key key(sz, n);
	int cnt = minMulti(sz, n);
	int mn = mem[key].second;
	int pos = apply(n % mn, s, buf);
	buf[pos + 0] = "0123456789"[mn];
	buf[pos + 1] = '[';
	pos += 2;
	pos += apply(n / mn, s, buf + pos);
	buf[pos++] = ']';
	return pos;
}

string sD;
string sF;
string sDB;
string sBF;
string sEACD;
string sBDBFB;
string sBDBFF;

char bufPR[200000];
int applyPR(lol n, char *buf) {
	if (1 == n) {
		return apply(1, sEACD, buf);
	}
	int pos = 0;
	pos += apply(n, sF, bufPR + pos);
	pos += apply(n, sDB, bufPR + pos);
	bufPR[pos++] = 'D';
	bufPR[pos] = 0;

	pos = apply(n, bufPR, pos, buf);
	return pos;
}

int applyTR(lol n, char *buf) {
	if (n <= 2) {
		if (1 == n) {
			buf[0] = 'B';
			return 1;
		}
		if (2 == n) {
			return apply(1, sBDBFB, buf);
		}
	}
	lol k = (n - 1) / 2;
	int pos = 0;

	buf[pos++] = '2';
	buf[pos++] = '[';
	pos += applyTR(k, buf + pos);
	buf[pos++] = ']';

	pos += apply(k, sD, buf + pos);

	pos += applyPR(k, buf + pos);

	if (n % 2 != 0) {
		pos += apply(k*2, sBF, buf + pos);
		buf[pos++] = 'B';
	} else {
		pos += apply(k*2, sBDBFF, buf + pos);
		pos += apply(1, sBDBFB, buf + pos);
	}
	return pos;
}

void init() {
	sD = string("D");
	sF = string("F");
	sDB = string("DB");
	sBF = string("BF");
	sEACD = string("EACD");
	sBDBFB = string("BDBFB");
	sBDBFF = string("BDBFF");
}

char res[900000];
int main() {
	init();

	lol n;
	scanf("%lld", &n);

	int pos = 0;
	pos += applyTR(n, res + pos);
	pos += apply(n, sD, res + pos);
	pos += apply(n, sF, res + pos);
	res[pos] = 0;
	printf("%s\n", res);

	return 0;
}