#include <iostream>
#include <bits/stdc++.h>

std::string find_operations(int N) {
    if (N == 1)
        return "";

    std::string operations;
    while (N > 1) {
        if ((N - 1) % 3 == 0) {
            N = (N - 1) / 3;
            operations += 'B';
        } else {
            N = (N - 1) / 2;
            operations += 'A';
        }
    }
    // Reverse the string to get operations from x=1 to x=N
    reverse(operations.begin(), operations.end());
    return operations;
}

int main() {
    int N;
    std::cin >> N;
    
    std::string result = find_operations(N);
    std::cout << result << std::endl;

    return 0;
}