#if defined(ONPC) && !defined(_GLIBCXX_ASSERTIONS)
#define _GLIBCXX_ASSERTIONS
#endif
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/detail/standard_policies.hpp>
#ifdef ONPC
#include "t_debug.cpp"
#else
#define debug(...) 42
#endif
#define allit(a) (a).begin(), (a).end()
#define sz(a) ((int) (a).size())
#include "combo.h"
using namespace std;
using ll = long long;
using vi = vector<int>;
namespace pd = __gnu_pbds;
template<typename K>
using ordered_set = pd::tree<K, pd::null_type, less<int>, pd::rb_tree_tag, pd::tree_order_statistics_node_update>;
template<typename... T>
using gp_hash_table = pd::gp_hash_table<T...>;//simple using statement gives warnings
const int INF = 1e9;
const ll INFL = 1e18;
const int N = 1e5;
const int RANDOM = chrono::high_resolution_clock::now().time_since_epoch().count();
mt19937 rng(RANDOM);
string order = "ABXY";
void shuffle() {
for (int i = 0; i < sz(order)-1; i++) {
swap(order[i], order[i + rng()%(sz(order)-i)]);
}
}
string guess_sequence(int n) {
string res;
shuffle();
if (press(order.substr(0, 2))) {
if (press(order.substr(0, 1))) res += order[0];
else res += order[1];
} else {
if (press(order.substr(2, 1))) res += order[2];
else res += order[3];
}
for (int i = 0, j = 0; i < sz(order); i++) {
if (order[i] != res.front()) order[j++] = order[i];
}
order.resize(sz(order)-1);
for (int i = 1; i < n; i++) {
shuffle();
if (press(res + order[0] + res + order[1]) == i+1) {
if (press(res + order[0]) == i+1) res += order[0];
else res += order[1];
} else {
res += order[2];
}
}
return res;
}
