#include<bits/stdc++.h>
#include "combo.h"
#define ll long long
#define ld long double
#define ff first
#define ss second
#define pb push_back
#define vr(v) v.begin(),v.end()
#define rv(v) v.rbegin(),v.rend()
//mt19937 myrand(373);
using namespace std;
namespace davit {
mt19937 myrand(chrono::steady_clock::now().time_since_epoch().count());
ll RANDOM(ll l, ll r) {
ll res = myrand() % (r - l + 1) + l;
return res;
}
void shuffle(vector<char> &a) {
for (int i = 0; i < (int) a.size(); i++) {
int idx = RANDOM(0, (int) a.size() - 1);
swap(a[i], a[idx]);
}
}
};
string guess_sequence(int N) {
int coins = press("AB");
string answer;
if (coins) {
if (press("A"))answer = "A";
else answer = "B";
} else {
if (press("X"))answer = "X";
else answer = "Y";
}
vector<char> combo;
for (char x: {'A', 'B', 'X', 'Y'}) {
if (to_string(x) != answer)combo.pb(x);
}
for (int i = 0; i < N - 1; i++) {
davit::shuffle(combo);
for (int j = 0; j < (int) combo.size(); j++) {
if (j == (int) combo.size() - 1) {
answer += combo[j];
break;
}
string tmp = answer + combo[j];
int pts = press(tmp);
if (pts == (int) tmp.size()) {
answer += combo[j];
break;
}
}
}
return answer;
}
