#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
#define ll int
#define ld double
#define endl '\n'
#define fi first
#define se second
#define pb push_back
#define REP(i,r) for(ll i=0,_r=(r);i<_r;i++)
#define FOR(i,l,r) for(ll i=(l),_r=(r);i<=_r;i++)
#define FORE(i,v) for(__typeof((v).begin()) i=(v).begin();i!=(v).end();i++)
#define FORNG(i,r,l) for(ll i=(r),_l=(l);i>=_l;i--)
#define MASK(i) (1LL<<(i))
#define BIT(x,i) (((x)>>(i))&1LL)
#define all(v) (v).begin(),(v).end()
#define size(v) ((ll)(v).size())
char ch[] = {'A', 'B', 'X', 'Y'};
string p = "";
// ll press(string s){}
char guess_one_char(){
if(press(p + "A" + p + "B") > size(p)){
if(press(p + "A") > size(p))return 'A';
return 'B';
}else{
if(press(p + "X") > size(p))return 'X';
}
return 'Y';
}
string guess_sequence(int n) {
p += guess_one_char();
vector<char> d;
for(char x : ch)if(p[0] != x)d.pb(x);
FOR(i,2,n - 1){
ll tmp = press(p + d[0] + p + d[1] + d[0] + p + d[1] + d[1] + p + d[1] + d[2]);
if(tmp == size(p)){
p += d[2];
}
if(tmp == size(p) + 1){
p += d[0];
}
if(tmp == size(p) + 2){
p += d[1];
}
}
if(size(p) != n)p += guess_one_char();
return p;
}
