#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string guess_sequence(int n)
{
string p = "", ans = "" ;
char a, b, c, d;
if (press("AB") > 0 )
{
c = 'X', d = 'Y' ;
press("A")? (a = 'A', b = 'B') : (a = 'B', b = 'A');
}
else
{
c = 'A', d = 'B' ;
press("X")? (a = 'X', b = 'Y') : (a = 'Y', b = 'X');
}
ans=a;
if (n == 1) return ans;
for (int i=1; i<n-1; ++ i)
{
p = ans + b + b + ans + b + c + ans + b + d + ans + c;
int bk = press(p);
if (bk == i + 0 ) ans += d;
if (bk == i + 1 ) ans += c;
if (bk == i + 2 ) ans += b;
}
if (press(ans + b) == n) ans += b;
else if (press(ans + c) == n) ans += c;
else ans += d;
return ans;
}
