#include<bits/stdc++.h>
using namespace std;
const long long N=2e5+5;

string cal(string S,long long x){
	if(!x) return "";
	if(x==1) return S;
	if(x>9) return "9["+cal(S,x/9)+"]"+cal(S,x%9);
	else{
		if(S.size()>1) return to_string(x)+"["+S+"]";
		else return to_string(x)+S;
	}
}

string solve(long long n){
	string S;
	if(n==1) return "FB";
	if(n%2==0) return cal("F",n)+cal("BD",n-1)+"B"+solve(n-1);
	long long m=(n-1)/2;
	return cal("F",n)+cal(cal("B",m+1)+cal("DF",m)+"D",m)+cal("BD",m)+"B"+cal(solve(m),2);
}

int main(){
	long long n;
	cin>>n;
	cout<<solve(n)+cal("D",n);
}