# include <bits/stdc++.h>
using namespace std;
# define ll long long
# define ld long double
# define pb push_back
# define pob pop_back
# define mp make_pair
# define fi first
# define se second
# define all(x) x.begin(),x.end()
# define ts to_string
# define ti(a) atoi(a.c_str())
# define NumAfterDecimalP(x) cout<<setprecision(x)<<fixed
const ld pi = 2*acos(0.0);
const ll inf = LLONG_MAX;
const ll mod = 1e9+7;
#include "combo.h"
std::string guess_sequence(int N) {
string ans="";
for(int i=1; i<=N; i++){
ans+="A";
ll kj1=press(ans);
if(kj1==i) continue;
ans.pop_back();
ans+="B";
ll kj2=press(ans);
if(kj2==i) continue;
ans.pop_back();
ans+="X";
ll kj3=press(ans);
if(kj3==i) continue;
ans.pop_back();
ans+="Y";
}
return ans;
}
