#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
vector<char> C;
int query(string s, array<vector<int>, 3> v) {
string p = "";
for (int i = 0; i < 3; i++) {
p += C[3] + s;
for (int x : v[i])
p += C[x];
}
return press(p);
}
vector<int> operator+(vector<int> f, vector<int> s) {
for (int x : s)
f.push_back(x);
return f;
}
void pop_front(vector<int> &v) {
vector<int> nv;
for (int i = 1; i < v.size(); i++)
nv.push_back(v[i]);
v = nv;
}
string guess_sequence(int N) {
if (press("AB")) {
if (press("A"))
C = {'B', 'X', 'Y', 'A'};
else
C = {'A', 'X', 'Y', 'B'};
}
else {
if (press("X"))
C = {'Y', 'B', 'A', 'X'};
else
C = {'X', 'B', 'A', 'Y'};
}
if (N == 1)
return string{C[3]};
if (N == 2) {
string p = "";
p += C[3], p += C[0], p += C[3], p += C[1];
if (press(p) == 1)
return string{C[3]} + string{C[2]};
p = string{C[3]} + string{C[0]};
if (press(p) == 2)
return p;
return string{C[3]} + string{C[1]};
}
string s = "";
array<vector<int>, 3> pos = {};
pos[0] = {0}, pos[1] = {1}, pos[2] = {2};
for (int i = 0; s.size() + pos[0].size() + 1 < N; i++) {
int c = query(s, {pos[0] + vector{0}, pos[0] + vector{1}, pos[1] + vector{0}}) - s.size() - pos[0].size();
if (c <= 0) {
for (int x : pos[2])
s.push_back(C[x]);
pos[0] = {0}, pos[1] = {1}, pos[2] = {2};
}
if (c == 1) {
decltype(pos) tpos;
tpos[0] = pos[1] + vector{1}, tpos[1] = pos[1] + vector{2}, tpos[2] = pos[0] + vector{2};
pos = tpos;
}
if (c == 2) {
decltype(pos) tpos;
tpos[0] = pos[0] + vector{0}, tpos[1] = pos[0] + vector{1}, tpos[2] = pos[1] + vector{0};
pos = tpos;
}
while (!pos[0].empty() && !pos[1].empty() && !pos[2].empty()) {
if (pos[0][0] == pos[1][0] && pos[1][0] == pos[2][0]) {
s.push_back(C[pos[0][0]]);
for (int x : {0, 1, 2})
pop_front(pos[x]);
}
else
break;
}
}
string s0, s1, s2;
s0 = s1 = s2 = C[3] + s;
for (int x : pos[0])
s0.push_back(C[x]);
for (int x : pos[1])
s1.push_back(C[x]);
for (int x : pos[2])
s2.push_back(C[x]);
if (press(s0) == N)
return s0;
if (press(s1) == N)
return s1;
return s2;
}
