#include "combo.h"
//#include "grader.cpp"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pb push_back
string ar[4] = {"A", "B", "X", "Y"};
string guess_sequence(int N){
string s, t;
string a, b, c, d;
int n = N;
if (press("AB")){
if (press("A"))
a = "A";
else
a = "B";
}
else {
if (press("X"))
a = "X";
else
a = "Y";
}
s = a;
if (N == 1)
return s;
int z = 0;
for (int i = 0; i < 4; i++){
if (ar[i] != a && z == 0){
b = ar[i];
z++;
}
else if (ar[i] != a && z == 1){
c = ar[i];
z++;
}
else if (ar[i] != a)
d = ar[i];
}
for (int i = 2; i < n; i++){
t = (s + b + b) + (s + b + c) + (s + b + d) + (s + c);
int r = press(t);
if (r == i + 1)
s += b;
else if (r == i)
s += c;
else
s += d;
}
t = (s + b) + (s + c);
if (press(t) == n){
if (press(s + b) == n)
s += b;
else
s += c;
}
else
s += d;
return s;
}
