#include "combo.h"
#include <vector>
using namespace std;
string guess_sequence(int N){
string G;
{ // find initial character
int t1 = press("AB");
if(t1 >= 1){
t1 = press("A");
G += (t1 >= 1 ? 'A' : 'B');
}
else{
t1 = press("X");
G += (t1 >= 1 ? 'X' : 'Y');
}
}
vector<string> letters;
for(auto x : {"A", "B", "X", "Y"}){
if(x[0] != G[0]) letters.push_back(x);
}
for(int i = 1; i < N - 1; i ++){
string q;
vector<string> vec;
vec.push_back(letters[0]);
vec.push_back(letters[1] + letters[0]);
vec.push_back(letters[1] + letters[1]);
vec.push_back(letters[1] + letters[2]);
for(auto add : vec){
q += G;
q += add;
}
int p = press(q);
if(p == (int)G.size() + 0) G += letters[2];
else if(p == (int)G.size() + 1) G += letters[0];
else if(p == (int)G.size() + 2) G += letters[1];
}
if(press(G + letters[0]) == N) return G + letters[0];
if(press(G + letters[1]) == N) return G + letters[1];
else return G + letters[2];
}
