#include<bits/stdc++.h>
#include "combo.h"
using namespace std;
std::string guess_sequence(int n) {
string s="ABXY",ans="";
if(press("AB")){
if(press("A")) ans+="A";
else ans+="B";
}
else{
if(press("X")) ans+="X";
else ans+="Y";
}
if(n==1) return ans;
for(int i=0;i<4;++i){
if(s[i]==ans[0]){
s.erase(s.begin()+i);
break;
}
}
for(int i=1;i<n-1;++i){
string p=ans+s[1];
for(auto c:s) p+=ans+s[2]+c;
ans+=s[press(p)-ans.length()];
}
if(press(ans+s[0])==n) ans+=s[0];
else if(press(ans+s[1])==n) ans+=s[1];
else ans+=s[2];
return ans;
}
