#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string guess_sequence(int N) {
// Guessing first letter
set<string> S;
S.insert("A"), S.insert("B"), S.insert("X"), S.insert("Y");
string p = "";
int ans = press("AB");
if (ans >= 1){
ans = press("A");
if (ans == 1) p = "A";
else p = "B";
} else {
ans = press("X");
if (ans == 1) p = "X";
else p = "Y";
}
if (N == 1) return p;
S.erase(p);
int c=0;
string B, X, Y;
for (auto x: S){
if (c == 0) B = x;
if (c == 1) X = x;
if (c == 2) Y = x;
c++;
}
// Guessing the other letters
int cnt=1;
for (int i=1;i<N-1;i++){
string trash = (p + B) + (p + X + Y) + (p + X + X) + (p + X + B);
ans = press(trash);
if (ans == cnt+1) p += B;
else if (ans == cnt+2) p += X;
else p += Y;
cnt++;
}
// Guessing last letter
ans = press(p + B + X);
if (ans == N-1){
ans = press(p+X);
if (ans == N) p += X;
else p += B;
} else {
p += Y;
}
return p;
}
