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