/*input
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include "combo.h"
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<vl> vll;
typedef vector<pi> vpi;
typedef vector<vpi> vpii;
typedef vector<pl> vpl;
typedef vector<cd> vcd;
typedef vector<bool> vb;
typedef vector<vb> vbb;
typedef string str;
typedef vector<str> vs;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)
#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define x first
#define y second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;
vs c = {"A", "B", "X", "Y"};
/*int press(str s){
cout << s << endl;
int a;
cin >> a;
return a;
}*/
str guess_sequence(int N){
str ats = "";
int a;
int curr = 0;
a = press(str(c[0] + c[1]));
if(a == 2){
ats = c[0] + c[1];
c.erase(c.begin());
curr += 2;
}
else if(a == 1){
a = press(c[0]);
if(a){
ats += c[0];
c.erase(c.begin());
}
else{
ats += c[1];
c.erase(c.begin() + 1);
}
curr++;
}
else{
a = press(c[2]);
if(a){
ats += c[2];
c.erase(c.begin() + 2);
}
else{
ats += c[3];
c.erase(c.begin() + 3);
}
curr++;
}
for(auto u: c) cout << u << " ";
cout << endl;
str aa = c[0] + c[0];
str ab = c[0] + c[1];
str ba = c[1] + c[0];
str bb = c[1] + c[1];
str ac = c[0] + c[2];
str bc = c[1] + c[2];
while(curr < N - 1){
a = press(ats + aa + ats + ab + ats + ba);
a -= curr;
if(!a){
ats += c[2];
curr++;
}
else if(a == 1){
a = press(ats + bb);
a -= curr;
if(!a){
ats += ac;
curr += 2;
}
else if(a == 1){
ats += bc;
curr += 2;
}
else if(a == 2){
ats += bb;
curr += 2;
}
}
else if(a == 2){
a = press(ats + aa);
a -= curr;
if(!a){
ats += ba;
curr += 2;
}
else if(a == 1){
ats += ab;
curr += 2;
}
else{
ats += aa;
curr += 2;
}
}
}
if(curr == N - 1){
a = press(ats + c[0] + ats + c[1]);
a -= curr;
if(a == 1){
a = press(ats + c[0]);
a -= curr;
if(a){
ats += c[0];
}
else{
ats += c[1];
}
curr++;
}
else{
ats += c[2];
curr++;
}
}
return ats;
}
/*int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int n;
cin >> n;
guess_sequence(n);
}*/
/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( )
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/
