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

string I(int n);
string III(int n);
string R(int n);
string Repeat(string s, int times); 
string Repeat_less_9(string s, int times);
vector <int> break_to_9(int n);

string I(int n)
{
    if (n == 0)
        return "";
    if (n == 1)
        return "A";
    
    string ans = "";
    ans += "A";
    ans += III(n - 2);
    ans += Repeat("EA", n - 1);
    ans += Repeat("CA", n - 1);

    return ans;
}

string III(int n)
{
    if (n == 0)
        return "";
    if (n == 1)
        return "AEC";
    
    string ans = "";
    if (n % 2 == 0)
    {
        ans += Repeat_less_9(I(n / 2), 2);
        ans += Repeat("E", n / 2);
        ans += R(n / 2);
        ans += Repeat("C", n / 2);
        return ans;
    }

    ans += "A";
    ans += III(n - 1);
    ans += Repeat("EA", n - 1);
    ans += "E";
    ans += Repeat("C", n);
    return ans;
}

string R(int n)
{
    if (n == 0)
        return "";
    
    string ans = "";
    ans += Repeat(Repeat("DF", n - 1) + "D" + Repeat("B", n), n);
    ans += Repeat("F", n);
    ans += Repeat("E", n);
    ans += Repeat("C", n);
    return ans;
}

vector <int> break_to_9(int n)
{
    vector <int> ans;
    while (n > 0){
        ans.push_back(n % 9);
        n -= (n % 9);
        n /= 9;
    }

    reverse(ans.begin(), ans.end());
    return ans;
}

string Repeat_less_9(string s, int times)
{
    if (times == 0)
        return "";
    if (times == 1)
        return s;
    
    if (s.size() == 0)
        return "";
    if (s.size() == 1)
        return to_string(times) + s;

    string ans = to_string(times) + "[" + s + "]";
    return ans;
}

string Repeat(string s, int times)
{
    vector <int> v = break_to_9(times);
    string ans = "";

    for (int i : v){
        ans = Repeat_less_9(s, i) + Repeat_less_9(ans, 9);
    }

    return ans;
}

int32_t main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int n;
    cin >> n;

    cout << III(n) << "\n";
    return 0;
}