#include "combo.h"
#include <cassert>
#include <string>
#include <vector>
using namespace std;
string guess_sequence(int N)
{
string S, opt;
if (press("A")) opt="BXY", S="A";
else if (press("B")) opt="AXY", S="B";
else if (press("X")) opt="ABY", S="X";
else if (press("Y")) opt="ABX", S="Y";
if (N == 1) return S;
for (int i = 1; i < N - 1; ++i)
{
string ask = S + opt[0] + opt[0] + S + opt[0] + opt[1] + S + opt[0] + opt[2] + S + opt[1];
int k = press(ask);
if (k == i + 2) S += opt[0];
else if (k == i + 1) S += opt[1];
else S += opt[2];
}
if (press(S+opt[0])==N) S+=opt[0];
if (press(S+opt[1])==N) S+=opt[1];
if (press(S+opt[2])==N) S+=opt[2];
return S;
}
