#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
string guess_sequence(int N) {
string res = "";
if (press("AB") >= 1) {
if (press("A") == 1) {
res += "A";
} else {
res += "B";
}
} else {
if (press("X") == 1) {
res += "X";
} else {
res += "Y";
}
}
string notFirst;
for (ll i = 0; i < 4; i++) {
if ("ABXY"[i] == res[0]) continue;
notFirst.push_back("ABXY"[i]);
}
if (N == 1) {
return res;
}
for (ll i = 1; i < N - 1; i++) {
ll coins = press(res + notFirst[0] + res + notFirst[1] + notFirst[0] + res + notFirst[1] + notFirst[1] + res + notFirst[1] + notFirst[2]);
if (coins == N) { // res + notFirst[2]
res.push_back(notFirst[2]);
} else if (coins == N + 1) { // res + notFirst[0]
res.push_back(notFirst[0]);
} else { // res + notFirst[1]
res.push_back(notFirst[1]);
}
}
if (press(res + "AB") == 1) {
if (press(res + "A") == 1) {
res += "A";
} else {
res += "B";
}
} else {
if (press(res + "X") == 1) {
res += "X";
} else {
res += "Y";
}
}
return res;
}
