#include "combo.h"
#include <iostream>
#include <algorithm>
#include <cstring>
#include <iomanip>
#include <fstream>
#include <cmath>
#include <vector>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <map>
#include <stack>
#include <queue>
#include <assert.h>
#include <limits>
#include <cstdio>
#include <complex>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
#define mp make_pair
#define f first
#define s second
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<ld> vd;
typedef vector<str> vs;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<pd> vpd;
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pf push_front
#define pb push_back
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)
const int MOD = 1e9+7; // 998244353; // = (119<<23)+1
const int MX = 2e5+5;
const ll INF = 1e18;
const ld PI = 4*atan((ld)1);
const int dx[4] = {0,1,0,-1}, dy[4] = {1,0,-1,0};
std::string guess_sequence(int N) {
std::string S = "";
std::string p = "";
vector<char> nf;
if (press("AB")) {
if (press("A")) {
S+="A";
nf = {'B', 'X', 'Y'};
} else {
S+="B";
nf = {'A', 'X', 'Y'};
}
} else {
if (press("X")) {
S+="X";
nf = {'B', 'A', 'Y'};
} else {
S+="Y";
nf = {'B', 'X', 'A'};
}
}
if (N == 1) {
return S;
}
FOR (i, 2, N) {
p = S+nf[0]+S+nf[1]+nf[0]+S+nf[1]+nf[1]+S+nf[1]+nf[2];
ll res = press(p);
if (res == S.length()) {
S+=nf[2];
} else if (res == S.length()+1) {
S+=nf[0];
} else {
S+=nf[1];
}
}
if (press(S+nf[0]) == N) {
S+=nf[0];
} else if (press(S+nf[1]) == N) {
S+=nf[1];
} else {
S+=nf[2];
}
return S;
}
