#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
using ll = long long;
using pi = pair<int, int>;
using pl = pair<long long, long long>;
using vi = vector<int>;
using vl = vector<long long>;
using vpi = vector<pair<int, int>>;
using vpl = vector<pair<long long, long long>>;
#define fur(i, a, b) for(ll i = a; i <= (ll)b; ++i)
#define ruf(i, a, b) for(ll i = a; i >= (ll)b; --i)
#define fr first
#define sc second
#define mp make_pair
#define pb emplace_back
#define nl "\n"
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
string guess_sequence(int N) {
char c[] = {'A', 'B', 'X', 'Y'};
string ans, cur;
fur(i, 0, 2) {
for(auto u : c) {
cur.push_back(u);
if(press(cur) == i + 1) {
ans.push_back(u);
break;
}
cur.pop_back();
}
}
return ans;
}
