#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
string guess_sequence(int n)
{
string all = "ABXY",pos,ans;
if(press("AB"))
{
if(press("A")) ans = "A";
else ans = "B";
}
else
{
if(press("X")) ans = "X";
else ans = "Y";
}
if(n==1) return ans;
for(int i = 0;i < 4;i++) if(all[i]!=ans[0]) pos = pos+all[i];
for(int i = 1;i < n-1;i++)
{
string tmp = ans+pos[0];
for(int j = 0;j < 3;j++) tmp+=ans+pos[1]+pos[j];
int ret = press(tmp);
if(ret==i) ans+=pos[2];
else if(ret==i+1) ans+=pos[0];
else ans+=pos[1];
}
if(press(ans+pos[0]+ans+pos[1])==n)
{
if(press(ans+pos[0])==n) ans+=pos[0];
else ans+=pos[1];
}
else ans+=pos[2];
return ans;
}
