#include "bits/stdc++.h"
#include "combo.h"
using namespace std;
#define ll long long
std::string guess_sequence(int N) {
// std::string p = "";
// for (int i = 0; i < 4 * N; ++i) {
// p += 'A';
// }
// int coins = press(p);
// std::string S = "";
// for (int i = 0; i < N; ++i) {
// S += 'A';
// }
// return S;
string s = "";
if(press("A"))
{
s += 'A';
}
else if(press("B"))
{
s += 'A';
}
else if(press("X"))
{
s += 'A';
}
else if(press("Y"))
{
s += 'A';
}
if(N == 1)
{
return s;
}
vector<char> moves1{'A','B','X','Y'};
for(int i=1;i<N;++i)
{
for(int j=0;j<4;++j)
{
if(moves1[j] != s[0] and press(s + moves1[j]) == i + 1)
{
s += moves1[j];
}
}
}
return s;
}
