#include <bits/stdc++.h>
#include <chrono>
#define rep(i,n) for(int i = 0; i < n; i++)
#define rrep(i,a,b) for(int i = a; i < b; i++)
#define all(A) (A).begin(),(A).end()
#define MOD 1000000007
#define grt greater<int>()
#define mapf(M) for(auto& [k,v] : M)
using namespace std;
using ll = long long;
using P = pair<ll,ll>;
using pq = priority_queue<ll,vector<ll>,greater<ll>>;
ll INF = 1LL<<60;
template <typename T>
bool chmax(T &a,T &b){ if(a < b){ a = b; return true; } return false; }
template <typename T>
bool chmin(T &a,T &b){ if(a > b){ a = b; return true; } return false; }
struct Edge { int to; int cost; int from; };
using Graph = vector<vector<Edge>>;
using vi = vector<int>;

string ans,s = "";
void dfs(string s,int i){
	if(i == 1){
		ans = s;
		return;
	}

	i--;
	if(i%2 == 0) dfs(s+'A',i/2);
	if(i%3 == 0) dfs(s+'B',i/3);
}

int main(void){
	int n; cin >> n;
	dfs(s,n);
	reverse(all(ans));
	cout << ans;
}