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

long long N;
vector<string> ans_all;

void dfs(long long x, string S) {
  if(x == 1) {
    ans_all.push_back(S);
  }else {
    if((x - 1) % 2 == 0) dfs((x - 1) / 2, 'A' + S);
    if((x - 1) % 3 == 0) dfs((x - 1) / 3, 'B' + S);
  }
}

int main() {
  cin >> N;
  dfs(N, "");
  assert(ans_all.size() == 1);
  cout << ans_all[0] << endl;
}