# 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;
ll c1=press("A"),c2=press("B"),c3=press("X");
bool a=true,b=true,x=true;
if(c1==1) a=false,ans+="A";
else if(c2==1) b=false,ans+="B";
else if(c3==1) x=false,ans+="X";
else
ans+="Y";
for(int i=2; i<=N; i++){
if(a && b && x){
ans+="A";
ll ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="B";
ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="X";
}
else if(a && b && !x){
ans+="A";
ll ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="B";
ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="Y";
}
else if(a && !b && x){
ans+="A";
ll ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="X";
ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="Y";
}
else{
ans+="B";
ll ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="X";
ch=press(ans);
if(ch==i) continue;
ans.pop_back();
ans+="Y";
}
}
return ans;
}
