#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>;

void dfs(string s,string& ans,int x,int n){
	if(n == x) return;

	if(x*2+1 <= n){
		s.push_back('A');
		dfs(s,ans,x*2+1,n);
		if(x*2+1 == n) ans = s;
		s.pop_back();
	}
	if(x*3+1 <= n){
		s.push_back('B');
		dfs(s,ans,x*3+1,n);
		if(x*3+1 == n) ans = s;
		s.pop_back();
	}
	return;
}

int main(void){
	int n; cin >> n;
	string ans = "",s = "";
	int x = 1;
	dfs(s,ans,x,n);
	cout << ans;
}