#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long int
#define rep(i, a, b) for(ll i = a; i < b; i++)
#define rep_(i, a, b) for(ll i = a; i > b; i--)
#define pb push_back
#define eb emplace_back
#define all(x) x.begin(), x.end()
#define vll vector<ll>
#define vvll vector<vll>
#define pll pair<ll, ll>
constexpr ll mod = 1e9+7, inf = LLONG_MAX;
string guess_sequence(int n) {
string s(n, '_');
{
ll c = press("AB");
if(c){
c = press("A");
s[0] = c?'A':'B';
}else{
c = press("X");
s[0] = c?'X':'Y';
}
}
string u = "BXY";
if(s[0]=='B') u = "AXY";
else if(s[0]=='X') u = "ABY";
else if(s[0]=='Y') u = "ABX";
string last(1, s[0]);
for(ll i = 1; i < n-1; ++i){
string cur = (last+u[0]+u[0])
+(last+u[0]+u[1])
+(last+u[0]+u[2])
+(last+u[1]);
// cout << "-- " << last << "\n";
ll cnt = press(cur);
ll sz = last.size();
if(cnt==sz+2) last += u[0];
else if(cnt==sz+1) last += u[1];
else last += u[2];
s[i] = last.back();
}
if(n>1){
ll c = press(last+u[0]+u[1]);
if(c>(ll)last.size()){
c = press(last+u[0]);
s[n-1] = c==(ll)last.size()+1?u[0]:u[1];
}else{
s[n-1] = u[2];
}
}
return s;
}
