#include<bits/stdc++.h>
#include "combo.h"
using namespace std;
string guess_sequence(int n){
string a = "A", b = "B", x = "X", y = "Y", res = "";
if (press(a)){
res += a;
a = y;
}
else if (press(b)){
res += b;
b = y;
}
else if (press(x)){
res += x;
x = y;
}
else
res += y;
for (int i = 2; i < n; ++i){
int val = press(res + a + res + b + a + res + b + b + res + b + x);
if (val == i)
res += a;
else if (val == i - 1)
res += x;
else
res += b;
}
if (n - 1){
if (press(res + a))
res += a;
else if (press(res + b))
res += b;
else res += x;
}
return res;
}
