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

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

    long long N; cin >> N;
    string answer = "";
    while(N != 1){
        long long left = (N-1);
        if(left%2 == 0) answer += "A",N = --N/2;
        else answer += "B",N = --N/3;

    }
    reverse(answer.begin(),answer.end());
    cout << answer << endl;
}