#include "combo.h"
#include<bits/stdc++.h>
using namespace std;
string guess_sequence(int N) {
string s; vector<char> dict;
switch(press("AB")) {
case 2:
s += "AB";
dict = {'B', 'X', 'Y'};
break;
case 1:
if(press("A")) s += "A", dict = {'B', 'X', 'Y'};
else s += "B", dict = {'A', 'X', 'Y'};
break;
case 0:
if(press("X")) s += "X", dict = {'A', 'B', 'Y'};
else s += "Y", dict = {'A', 'B', 'X'};
}
while(N - s.size() > 1) {
int p = press(s + dict[0] + dict[0] + s + dict[0] + dict[1] + s + dict[0] + dict[2] + s + dict[1]) - s.size();
if(p == 2) s += dict[0];
if(p == 1) s += dict[1];
if(p == 0) s += dict[2];
}
int p = press(s + dict[0] + s + dict[1]) - s.size();
if(p == 0)
s += dict[2];
else {
if(press(s + dict[0]) == N) s += dict[0];
else s += dict[1];
}
return s;
}
