#include "combo.h"
#include <iostream>
#include <string>
using namespace std;
string guess_sequence(int N) {
string s = "\0";
int ask = press("AB");
if (ask == 2) s = "AB";
else {
if (ask == 1) {
ask = press("A");
if (ask == 1) s = "A";
else s = "B";
} else {
ask = press("X");
if (ask == 1) s = "X";
else s = "Y";
}
}
if (s.size() == N) return s;
string A = (s[0] == 'A' ? "B" : "A");
string B = (s[0] <= 'B' ? "X" : "B");
string C = (s[0] <= 'X' ? "Y" : "X");
while ((int)s.size() + 1 < N) {
ask = press(s + A + A + s + A + B + s + A + C + s + B);
if (ask == (int)s.size() + 2) s += A;
else if (ask == (int)s.size() + 1) s += B;
else s += C;
}
ask = press(s + A);
if (ask == N) s += A;
else {
ask = press(s + B);
if (ask == N) s += B;
else s += C;
}
return s;
}
