#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string guess_sequence(int N){
string S;
char start;
int a = press("AB");
if(a == 2){
start = 'A';
}
else if(a == 1){
if(press("B") == 1) start = 'B';
else start = 'A';
}
else if(press("X") == 1) start = 'X';
else start = 'Y';
S += start;
vector<char> c;
if(start != 'A') c.push_back('A');
if(start != 'B') c.push_back('B');
if(start != 'X') c.push_back('X');
if(start != 'Y') c.push_back('Y');
for(int i = 1; i < N - 1; i++){
int q = press(S + c[0] + S + c[1] + c[0] + S + c[1] + c[1] + S + c[1] + c[2]);
if(q == i + 1) S += c[0];
else if(q == i + 2) S += c[1];
else S += c[2];
}
if(S.size() == N - 1){
if(press(S + c[0]) == N) S += c[0];
else if(press(S + c[1]) == N) S += c[1];
else S += c[2];
}
return S;
}
