#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
int best = 0;
string ans;
vector<char> ch{'A','B','X','Y'};
void backtrack(string &p,int &n)
{
if(p.size() > 4 * n)
{
return;
}
int a = press(p);
if(a > best)
{
best = a;
ans = p;
}
if(best==n)
{
return;
}
for(int i=0;i<4;++i)
{
if(p[0] != ch[i])
{
p+=ch[i];
backtrack(p,n);
p.pop_back();
}
}
}
string guess_sequence(int N) {
string p = "";
vector<bool> vis(4,0);
for(int i=0;i<4;++i)
{
p+=ch[i];
backtrack(p,N);
p.pop_back();
}
return ans;
}
