#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
#define ll long long
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
//using mint = modint998244353;
const int dx[4]={0,1,0,-1};
const int dy[4]={1,0,-1,0};

ll n;
string f(ll x, string a) {
    if (x == 1) return a;
    if((x-1ll)%2ll==0){
        string res = f((x-1ll)/2ll, a + 'A');
        if (!res.empty()){
            
            return res;
        }
    }    
    if((x-1ll)%3ll==0){
        string res2 = f((x-1ll)/ 3ll, a + 'B');
        if (!res2.empty()){
            
            return res2;
        }
    }
    
    return ""; 
}

int main() {
    cin >> n;
    ll x = 1;
    string a;
    a = f(n, "");
    reverse(a.begin(),a.end());
    cout << a << endl; 
    return 0;
}