#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
std::string guess_sequence(int N) {
string s;
string ans;
auto second_subtask = [&](int n){
string cur = "ABXY";
string s;
string ans;
for (int i = 0;i<4;++i){
string t;
t+=cur[i];
if (press(t) == 1){
for (int j = 0;j<4;++j){
if (i == j)continue;
s+=cur[j];
}
ans+=cur[i];
break;
}
}
for (int i = 0;i<n - 1;++i){
for (int j = 0;j<3;++j){
ans+=s[j];
if (press(ans) == i + 2){
break;
}
ans.pop_back();
}
}
return ans;
};
string v = second_subtask(N);
//cout<<v<<'\n';
return v;
}
