#include "combo.h"
using namespace std;
#include <string>
#include <vector>
#include <set>
string guess_sequence(int N) {
string ans = "";
set<string> strs = {"A", "B", "X", "Y"};
int ab = press("AB");
if(ab >= 1){
int a = press("A");
if(a == 1){
ans = "A";
}
else ans = "B";
}
else{
int x = press("X");
if(x == 1){
ans = "X";
}
else ans = "Y";
}
strs.erase(ans);
vector<string> left;
for(string s : strs){
left.emplace_back(s);
}
string first = ans;
for(int i = 1; i < N - 1; ++i){
int cur = press(ans + left[1] + ans + left[2] + left[0] + ans + left[2] + left[1] + ans + left[2] + left[2]);
if(cur == 1){
ans += left[0];
}
else if(cur == 2){
ans += left[1];
}
else ans += left[2];
}
ab = press(ans + "A" + ans + "B");
if(ab >= N){
int a = press(ans + "A");
if(a >= N){
ans += "A";
}
else ans += "B";
}
else{
int x = press(ans + "X");
if(x >= N){
ans += "X";
}
else ans += "Y";
}
return ans;
}
