#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
using ll = long long;

constexpr int iINF = 1'000'000'000;
constexpr ll llINF = 1'000'000'000'000'000'000;

int main () {
    ll N; cin >> N;

    bool end = false;
    int depth = -1;
    vector<char> ans(128);

    auto dfs = [&](auto self, int d, ll val) -> void {
        if (end) return;
        if (val == 1) {
            depth = d;
            end = true;
            return;
        }

        if (!end && (val - 1) % 2 == 0) {
            ans[d] = 'A';
            self(self, d + 1, (val - 1) / 2);
        }

        if (!end && (val - 1) % 3 == 0) {
            ans[d] = 'B';
            self(self, d + 1, (val - 1) / 3);
        }
    };

    dfs(dfs, 0, N);

    for (int i = depth - 1; 0 <= i; i--) {
        cout << ans[i];
    }
    cout << "\n";
}