#include <bits/stdc++.h>
#include "combo.h"
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define all(X) X.begin(), X.end()
#define allr(X) X.rbegin(), X.rend()
#define pb push_back
#define endl '\n'
using namespace std;
using namespace __gnu_pbds;
int press(string p);
string guess_sequence(int n){
string res = "";
string s = "ABXY";
for (ll i = 0; i < 4; i++) {
if (press(string(1, s[i])) == 1) {
res = s[i];
s.erase(s.begin() + i);
break;
}
}
for (ll i = 1; i < n; i++) {
char a = s[0], b = s[1], c = s[2];
string temp = res + a + res + b;
ll cur = press(temp);
if (cur == res.size() + 1) res += a;
else if (cur == res.size() * 2 + 2) res += b;
else res += c;
}
return res;
}
