#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
// int press(string s){
// if(s=="X") return 1;
// if(s=="XB") return 2;
// if(s == "XBA") return 3;
// return 0;
// }
string guess_sequence(int n){
string st = "";
char ct = 'A';
vector<char> cs = {'A','B','X','Y'};
for(auto z:cs){
char x = z;
string tmp = "";
tmp += x;
if(press(tmp)==1){
st = tmp;
ct = x;
break;
}
}
string ans = st;
vector<char> other = {'A','B','X','Y'};
auto ite = find(other.begin(),other.end(),ct);
other.erase(ite);
for(ll i=1;i<n;i++){
for(ll j=0;j<3;j++){
string tm = ans;
tm += other[j];
if(press(tm)==(i+1)){
ans = tm;
break;
}
}
}
return ans;
}
