#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
string guess_sequence(int N){
string res = "";
vector<string> v, k;
v.push_back("A");
v.push_back("B");
v.push_back("X");
v.push_back("Y");
if(press("AB")){
if(press("A")) res = "A";
else res = "B";
}else{
if(press("X")) res = "X";
else res = "Y";
}
for(string s: v){
if(s == res) continue;
k.push_back(s);
}
for (int i = 2; i < N; i++){
int kq = press(res + k[0] + res + k[1] + k[0] + res + k[1] + k[1] + res + k[1] + k[2]);
if(kq == i) res += k[0];
else if(kq == i + 1) res += k[1];
else res += k[2];
}
if(press(res + k[0]) == N) res += k[0];
else if(press(res + k[1]) == N) res += k[1];
else res += k[2];
return res;
}
