//#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
#define rep(i, n) for(int i=0; i<n; ++i)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
using namespace std;
using ll = int64_t;
using ld = long double;
using P = pair<int, int>;
using vs = vector<string>;
using vi = vector<int>;
using vvi = vector<vi>;
template<class T> using PQ = priority_queue<T>;
template<class T> using PQG = priority_queue<T, vector<T>, greater<T> >;
const int INF = 0xccccccc;
const ll LINF = 0xcccccccccccccccLL;
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true);}
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true);}
template<typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) { return is >> p.first >> p.second;}
template<typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) { return os << p.first << ' ' << p.second;}

#undef _GLIBCXX_DEBUG
string to_string(const string &s) {return '"' + s + '"';}
string to_string(const char *s) {return to_string(string(s));}
string to_string(bool b) {return b?"true":"false";}
string to_string(vector<bool> v) {
	string res = "{";
	for(int i = 0; i < int(v.size()); i++) {
		if(i) res += ", ";
		res += to_string(v[i]);
	}
	res += "}";
	return res;
}
template<size_t N>
string to_string(bitset<N> v) {
	string res;
	for(size_t i = 0; i < N; i++) res += char('0' + v[i]);
	return res;
}
template<class A, class B>
string to_string(pair<A, B>);
template<class A, class B, class C>
string to_string(tuple<A, B, C>);
template<class A, class B, class C, class D>
string to_string(tuple<A, B, C, D>);
template<class A>
string to_string(A v) {
	bool first = true;
	string res = "{";
	for(const auto &x:v) {
		if(!first) res += ", ";
		first = false;
		res += to_string(x);
	}
	res += "}";
	return res;
}
template<class A, class B>
string to_string(pair<A, B> p) {
	return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template<class A, class B, class C>
string to_string(tuple<A, B, C> t) {
	return "(" + to_string(get<0>(t)) + ", " + to_string(get<1>(t)) + ", " + to_string(get<2>(t)) + ")";
}
template<class A, class B, class C, class D>
string to_string(tuple<A, B, C, D> t) {
	return "(" + to_string(get<0>(t)) + ", " + to_string(get<1>(t)) + ", " + to_string(get<2>(t)) + ", " + to_string(get<3>(t)) + ")";
}
void debug_out() {cerr << endl;}
template<typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
	cerr << ' ' << to_string(H);
	debug_out(T...);
}
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 822
#endif

//head

array<int, 101> grundy;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	grundy[1] = 0;
	for(int i = 2; i < 101; i++) {
		vi mm;
		if(i&1) mm.emplace_back(grundy[i>>1]^grundy[(i>>1)+1]);
		else mm.emplace_back(0);
		switch (i%3) {
		case 0:
			mm.emplace_back(grundy[i/3]);
			break;
		case 1:
			mm.emplace_back(grundy[i/3+1]);
			break;
		default:
			mm.emplace_back(grundy[i/3]);
			break;
		}
		sort(all(mm));
		if(mm[0] == 0) {
			if(mm[1] == 1) grundy[i] = 2;
			else grundy[i] = 1;
		}
		else grundy[i] = 0;
	}
	for(int i = 1; i < 101; i++) {
		debug(i, grundy[i]);
	}
	int n;
	cin >> n;
	if(grundy[n]) cout << "A\n";
	else cout << "B\n";
}