#include <bits/stdc++.h>
#define all(A) (A).begin(),(A).end()
using namespace std;

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;
}