#include "combo.h"
#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define in insert
#define all(x) x.begin(),x.end()
#define pb push_back
#define eb emplace_back
#define ff first
#define ss second
string guess_sequence(int n) {
string S = "ABXY";
char st;
string tmp = "AB";
if(press(tmp)) {
tmp = "A";
if(press(tmp)) st = 'A';
else st = 'B';
} else {
tmp = "X";
if(press(tmp)) st = 'X';
else st = 'Y';
}
S.erase(find(all(S), st));
string ans = "";
ans.pb(st);
if(n == 1) return ans;
for(int i = 2; i <= n - 1; i++) {
string ask = "";
ask += ans;
ask.pb(S[0]);
for(int j = 0; j < 3; j++) {
ask += ans;
ask.pb(S[1]);
ask.pb(S[j]);
}
int l = press(ask);
if(l == i - 1) ans.pb(S[2]);
else if(l == i) ans.pb(S[0]);
else ans.pb(S[1]);
}
char en = S[2];
for(int i = 0; i < 2; i++) {
string ask = ans;
ask.pb(S[i]);
if(press(ask) == n) {
en = S[i];
break;
}
}
ans.pb(en);
return ans;
}
