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#include <bits/stdc++.h>

using namespace std;

typedef long long lld;

string base1[] { "", "A", "AEACA" };

string repeat(const string &s, lld times) {
    if (times == 0)
        return "";
    if (times < 10) {
        if (s.size() == 1)
            return times == 1 ? s : to_string(times) + s;
        if (times * s.size() <= s.size() + 3) {
            string res = "";
            while (times--) res += s;
            return res;
        }
        return to_string(times) + '[' + s + ']';
    }
    return "9[" + repeat(s, times / 9) + ']' + repeat(s, times % 9);
}

string tree1(lld n) {
    if (n <= 2) return base1[n];
    
    string res = n % 2 == 1 ? repeat("AE", n-1) + "A" : repeat("AAECE", n-2) + "AEACA";
    n = (n-1)/2;
    res += repeat(repeat("CA", n) + "C" + repeat("E", n), n) + repeat("C", n);
    return res + (n == 1 ? tree1(n) + tree1(n) : "2[" + tree1(n) + ']');
}

string draw(lld n) {
    return tree1(n) + repeat("E", n) + repeat("C", n);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    lld n;
    cin >> n;
    cout << draw(n) << '\n';
}