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#include<bits/stdc++.h>
using namespace std;

string repeat(int a, string w)
{
    string res = "";
    if(a == 0)
        return res;
    if(a <= 8)
    {
        if(a != 1)
        {
            res += (char)('0' + a);
            res += '[';
            res += w;
            res += ']';
        }
        else
            res += w;
        return res;
    }
    res += "9[";
    res += repeat(a / 9, w);
    res += ']';
    res += repeat(a % 9, w);
    return res;
}

string trojkat(int a)
{
    if(a == 1)
        return "BD";
    if(a == 2)
        return "BBDEACD";
    int duze = a;
    a--;
    if(a % 2)
        a--;
    a /= 2;
    string res = repeat(2, trojkat(a));
    res += repeat(a, "BF");
    string col = repeat(a - 1, "FD");
    col += 'F';
    col += repeat(a, "B");
    res += repeat(a, col);
    res += repeat(a, "D");
    res += repeat(a, "BF");
    res += 'B';
    res += repeat(a * 2 + 1, "D");
    if(a * 2 + 1 != duze)
    {
        res += repeat(a * 2 + 1, "BF");
        res += 'B';
        res += repeat(a * 2 + 2, "D");
    }
    return res;

}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int a;
    cin>>a;
    string res = trojkat(a);
    res += repeat(a, "F");
    cout<<res;

    return 0;
}