#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
using ll = long long;
using vi = vector<long long>;
#define pb emplace_back
std::string guess_sequence(int n) {
char first = ' ';
string res = "";
vector<char> left;
set<char> moves = {'A', 'B', 'X', 'Y'};
int ab = press("AB");
int ax = press("AX");
if(ab && ax)
first = 'A';
else if(ab)
first = 'B';
else if(ax)
first = 'X';
else
first = 'Y';
res += first;
moves.erase(first);
for(auto i : moves)
left.pb(i);
if(n == 1) return res;
for(int i = 1; i < n - 1; ++i) {
string try1 = res + left[0];
string try2 = res + left[1];
string try21 = try2 + left[0];
string try22 = try2 + left[1];
string try23 = try2 + left[2];
ll curr = press(try1 + try21 + try22 + try23);
if(curr == i + 2)
res += left[1];
else if(curr == i + 1)
res += left[0];
else
res += left[2];
}
ll try1 = press(res + left[0]);
if(try1 == n)
return res + left[0];
try1 = press(res + left[1]);
if(try1 == n)
return res + left[1];
return res + left[2];
}
