#include<bits/stdc++.h>
#include "combo.h"
//#include "grader.cpp"
using namespace std;
//#define int long long
//#define endl "\n"
#define all(v) v.begin(),v.end()
#define gen(arr,n,nxt) generate(arr,arr+n,nxt)
#define Blobo2 ios_base::sync_with_stdio(false);cin.tie(0);
char le[]={'A','B','X','Y'};
string guess_sequence(int n){
string t = "AB";
//cout<<t<<endl;
int x = press(t);
if(x == 2) t = "A";
else if(x){
t = "B";
//cout<<t<<endl;
x=press(t);
if(!x)
t = "A";
}
else{
t = "X";
//cout<<t<<endl;
x = press(t);
if(!x)
t = "Y";
}
int idx = 0;
for(int i=0;i<4;i++){
if(le[i] == t[0]){
idx = i;
break;
}
}
for(int i=1;i<n-1;i++){
string test;
test += t;
test += le[(idx+1)%4];
test += t;
test += le[(idx+2)%4];
test += le[(idx+1)%4];
test += t;
test += le[(idx+2)%4];
test += le[(idx+2)%4];
test += t;
test += le[(idx+2)%4];
test += le[(idx+3)%4];
//cout<<t<<' '<<t.size()<<endl;
x = press(test);
if(x == (int)t.size())
t += le[(idx+3)%4];
else if(x == (int)t.size()+1)
t += le[(idx+1)%4];
else
t += le[(idx+2)%4];
//cout<<t<<endl;
}
t += le[(idx+1)%4];
x = press(t);
if(x == n)
return t;
t.pop_back();
t += le[(idx+2)%4];
x = press(t);
if(x == n)
return t;
t.pop_back();
t += le[(idx+3)%4];
return t;
}
