#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
#define ii pair<int,int>
#define fi first
#define se second
#define ll long long
#define all(x) x.begin(),x.end()
#define sz(x) (int)x.size()
const int mxn = 1e5;
/*
int press(string s){
cout<<s<<"\n";
int x; cin>>x;
return x;
}
// */
string guess_sequence(int N) {
string s = "", left = "";
int ptr = 0;
int ask1 = press("AX");
int ask2 = press("BX");
if(ask1==ask2){
if(ask1==0)s="Y",left="ABX";
else s="X",left="ABY";
}else{
if(ask1)s="A",left="BXY";
else s="B",left="AXY";
}
ptr++;
if(N==1)return s;
while(ptr<N-1){
string now = (s+left[0])+(s+left[1]+left[0])+(s+left[1]+left[1])+(s+left[1]+left[2]);
int ask = press(now);
if(ask==ptr+1){
s += left[0];
}else if(ask==ptr+2){
s += left[1];
}else{
s += left[2];
}
ptr++;
}
ask1 = press(s+left[0]);
ask2 = press(s+left[1]);
if(ask1==N){
s+=left[0];
}else if(ask2==N){
s+=left[1];
}else{
s+=left[2];
}
return s;
}
/*
int main(){
//ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cout<<guess_sequence(3);
return 0;
}
// */
