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#include <bits/stdc++.h>
#define ll long long

const ll NINE = 9;

std::string draw_repeat(ll n, std::string s) {
    if (n == 0) return "";
    if (n == 1) {
        std::string z = s;
        return z;
    }
    ll r = n % NINE;
    n /= NINE;
    std::string z = "";
    if (n > 0) {
        z = "9[";
        z += draw_repeat(n, s);
        z += "]";
    }
    if (r > 0) {
        z += (char)(r + '0');
        if (s.length() == 1) {
            z += s;
        } else {
            z += "[";
            z += s;
            z += "]";
        }
    }
    return z;
}

std::string draw(ll n) {
    std::string s = "";
    if (n == 1) {
        s = "AEC";
    } else if (n == 2) {
        s = "AAECEAECC";
    } else if (n % 2 == 1) {
        s = draw_repeat(n, "A");
        s += draw_repeat(n-1, "EC");
        s += "E";
        s += draw(n-1);
        s += "C";
    } else {
        ll k = (n-2)/2;
        s = "F";
        std::string z = draw(k);
        z += draw_repeat(k, "BF");
        s += draw_repeat(2, z);
        s += draw_repeat(2*k, "FD");
        std::string t = draw_repeat(k, "B");
        s += t;
        std::string h = draw_repeat(k-1, "DF");
        h += "D";
        z = h + t; 
        s += draw_repeat(k-1, z);
        s += h; 
        s += draw_repeat(k+1, "F");
        s += draw_repeat(n, "B");
        s += "DFDB";
        s += draw_repeat(n-1, "D"); 
    }
    return s;
}

int main() {
    std::ios_base::sync_with_stdio(0); std::cin.tie(NULL);
    ll n; std::cin >> n;
    std::cout << draw(n) << "\n";
}