#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
std::string guess_sequence(int N) {
std::string s = "";
string ref = "ABXY";
int n = N;
// get first char
int coins= press("AB");
if(coins >= 1){
if(press("A") == 1){
s += "A";
}
else s += "B";
}
else{
if(press("X") == 1) s += "X";
else s += "Y";
}
if(n == 1) return s;
// only need to guess three other chars
string p = "";
for(auto e : ref) if(e != s[0]) p += e;
for(int i = 1; i < n - 1; i++){
string guess =
s + p[0] +
s + p[1] + p[0] +
s + p[1] + p[1] +
s + p[1] + p[2];
int coins = press(guess);
int gain = coins - i;
if(gain == 0){
s += p[2];
}
if(gain == 1){
s += p[0];
}
if(gain == 2){
s += p[1];
}
}
int cs = press(s + "AB");
if(cs >= N){
if(press(s + "A") == N){
s += "A";
}
else s += "B";
}
else{
if(press(s + "X") == 1) s += "X";
else s += "Y";
}
return s;
}
