#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string guess_sequence(int N) {
vector<string> guys = {"A", "B", "X", "Y"};
string s = "";
if (!press(guys[0] + guys[1])) {
swap(guys[0], guys[2]);
swap(guys[1], guys[3]);
}
if (!press(guys[0])) {
swap(guys[0], guys[1]);
}
s += guys[0];
if (N == 1) return s;
for (int i = 1; i < N-1; i++) {
string t = s + guys[2];
for (int i = 1; i < 4; i++) {
t += s + guys[3] + guys[i];
}
s += guys[press(t)-i+1];
}
if (press(s + guys[1]) == N) s += guys[1];
else if (press(s + guys[2]) == N) s += guys[2];
else s += guys[3];
return s;
}
