#include <bits/stdc++.h>
using namespace std;
#include "combo.h"
char OPTIONS[] = "ABXY";
string guess_sequence(int N) {
string curr = "";
if (press(curr + "A" + curr + "B") >= 1) {
if (press(curr + "A") >= 1) curr += "A";
else curr += "B";
} else {
if (press(curr + "X") >= 1) curr += "X";
else curr += "Y";
}
vector<char> rest;
for (int i = 0; i < 4; i++) {
if (OPTIONS[i] != curr[0]) rest.push_back(OPTIONS[i]);
}
for (int i = 1; i < N-1; i++) {
string s = curr + rest[0] + rest[0] + curr + rest[0] + rest[1] + curr + rest[0] + rest[2] + curr + rest[1];
int res = press(s);
if (res == i + 2) curr += rest[0];
else if (res == i + 1) curr += rest[1];
else curr += rest[2];
}
if (N > 1) {
if (press(curr + "A" + curr + "B") == N) {
if (press(curr + "A") == N) curr += "A";
else curr += "B";
} else {
if (press(curr + "X") == N) curr += "X";
else curr += "Y";
}
}
return curr;
}
