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#include <bits/stdc++.h>
#define dbg(x) " [" << #x << ": " << (x) << "] "
using namespace std;
template<typename A,typename B>
ostream& operator<<(ostream& out, const pair<A,B>& p) {
    return out << "(" << p.first << ", " << p.second << ")";
}
template<typename T>
ostream& operator<<(ostream& out, const vector<T>& c) {
    out << "{";
    for(auto it = c.begin(); it != c.end(); it++) {
        if(it != c.begin()) out << ", ";
        out << *it;
    }
    return out << "}";
}
string get(long long n, const string& s) {
    if(n == 0) return "";
    if(n == 1) return s;
    if(n <= 9 && s.length() == 1) return to_string(n) + s;
    if(n == 2) {
        if(s.length() == 2) return s + s;
        else return "2[" + s + "]";
    }
    if(n <= 9) return to_string(n) + "[" + s + "]";
    string r = get(n / 9, s);
    if(r.length() == 1) {
        r = "9" + r;
    } else {
        r = "9[" + r + "]";
    }
    r += get(n % 9, s);
    return r;
}
string solve(long long n, int a);
vector<string> x = {"A", "E", "C"};
string solve2(long long n, int a) {
    string r = x[a];
    if(n == 1) {
        return r;
    }
    r += solve(n - 2, a);
    r += get(n - 1, x[(a + 1) % 3] + x[a]);
    r += get(n - 1, x[(a + 2) % 3] + x[a]);
    return r;
}
string solve(long long n, int a) {
    if(n == 0) return "";
    if(n == 1) return x[a] + x[(a + 1) % 3] + x[(a + 2) % 3];
    string r = get(n / 2, x[a] + x[(a + 1) % 3]) + x[a] + get(n / 2, x[(a + 2) % 3]);
    r = get(n / 2, r);
    r += get(n / 2, x[a]);
    string s = solve2(n / 2, (a + 1) % 3);
    if(s.length() >= 3) r += "2[" + s + "]";
    else r += s + s;
    if(n & 1) {
        r += get(n - 1, x[a] + x[(a + 2) % 3]) + x[a];
        r += get(n, x[(a + 1) % 3]);
    }
    r += get(n, x[(a + 2) % 3]);
    return r;
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    long long n;
    cin >> n;
    cout << solve(n, 0) << endl;
    return 0;
}