#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
#define ll long long
std::string guess_sequence(int N) {
ll c=press("AB");
ll o=press("AX");
string s="";
vector<char>v;
if(c && o)
{
s+='A';
v.push_back('B');
v.push_back('X');
v.push_back('Y');
}
else if(c)
{
s+='B';
v.push_back('A');
v.push_back('X');
v.push_back('Y');
}
else if(o)
{
s+='X';
v.push_back('B');
v.push_back('Y');
v.push_back('A');
}
else
{
s+='Y';
v.push_back('B');
v.push_back('X');
v.push_back('A');
}
if(N==1)
{
return s;
}
for(int i=1;i<N-1;i++)
{
string z=s;
z+=v[0];
for(char x:v)
{
z+=s;
z+=v[1];
z+=x;
}
ll q=press(z);
if(q==s.size())
{
s+=v[2];
}
else if(q==s.size()+1)
{
s+=v[1];
}
else
s+=v[0];
}
if(press(s+v[0])==N)
{
return s+v[0];
}
else if(press(s+v[1])==N)
{
return s+v[1];
}
return s+v[2];
}