#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
string guess_sequence(int n) {
string ans="";
vector<char> c, cc = {'A', 'B', 'X', 'Y'};
bool found = 0;
for(int i = 0; i < 3; ++i){
if(press(ans+cc[i])){
ans.pb(cc[i]);
for(char cch : cc)
if(cch != cc[i]) c.pb(cch);
found = 1;
break;
}
}
if(!found){
ans.pb(cc[3]);
for(char cch : cc)
if(cch != cc[3]) c.pb(cch);
}
for(int i = 1; i < n; ++i){
found = 0;
for(int j = 0; j < 2; ++j){
if(press(ans + c[j]) == i+1){
found = 1;
ans.pb(c[j]);
break;
}
}
if(!found) ans.pb(c[2]);
}
return ans;
}
