#include <bits/stdc++.h>
#include <combo.h>
using namespace std;
#ifdef DEBUG
#include "../Library/debug.h"
#else
#define dbg(x...)
// #define cin fin
// #define cout fout
// const string FILE_NAME = ""; ifstream fin(FILE_NAME + ".in"); ofstream fout(FILE_NAME + ".out");
#endif
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) for (int i = 0; i < (a); ++i)
#define FORd(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define F0Rd(i, a) for (int i = (a) - 1; i >= 0; --i)
#define trav(a, x) for (auto& a : x)
#define f first
#define s second
#define pb push_back
#define sz(x) (int)(x).size()
#define all(x) x.begin(), x.end()
const char nl = '\n';
const int INF = 1e9;
const int MOD = 1e9 + 7;
string guess_sequence(int n){
string s = "";
string d = "ABXY";
bool dv[4];
F0R(i, 3){
if(press(string(1, d[i]))){
dv[i] = true;
s.pb(d[i]);
break;
}
}
if(sz(s) == 0){
s.pb(d[3]);
dv[3] = true;
}
FOR(i, 1, n){
string aux = s;
F0R(j, 4){
if(dv[j] == false){
aux.pb(d[j]);
break;
}
}
bool fir = true;
char x;
F0R(j, 4){
if(dv[j] == false && fir){
fir = false;
continue;
}
else if(dv[j] == false){
x = d[j];
}
}
F0R(j, 4){
if(dv[j] == false){
aux += s;
aux.pb(x);
aux.pb(dv[j]);
}
}
int nr = press(aux);
if(i + 2 == nr){
F0R(j, 4){
if(dv[j] == false){
s.pb(d[j]);
break;
}
}
}
else if(i + 3 == nr){
bool fi = true;
F0R(j, 4){
if(dv[j] == false && fi){
fi = false;
continue;
}
if(dv[j] == false){
s.pb(d[j]);
break;
}
}
}
else{
F0Rd(j, 4){
if(dv[j] == false){
s.pb(d[j]);
break;
}
}
}
}
return s;
}
/*
void solve(){
}
int32_t main(){
ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
int TC = 1;
// cin >> TC;
while(TC--){
solve();
}
return 0;
}
*/
