#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
string del(string s, char ch) {
string t;
for (auto &x : s) {
if (x != ch) {
t += x;
}
}
return t;
}
string mult(char ch, int x) {
string s;
for (int i = 1; i <= x; i++) {
s += ch;
}
return s;
}
string guess_sequence(int n) {
string sol;
string posi = "ABXY";
if (press(sol + posi[0] + posi[1]) > 0) {
if (press(sol + posi[0])) {
sol += posi[0];
} else {
sol += posi[1];
}
} else {
if (press(sol + posi[2])) {
sol += posi[2];
} else {
sol += posi[3];
}
}
posi = del(posi, sol[0]);
while ((int) sol.size() + 2 <= n) {
char a = posi[0];
char b = posi[1];
char c = posi[2];
int ret = press(sol + a + a + sol + a + b + sol + a + c + sol + b);
if (ret == (int) sol.size() + 2) {
sol += a;
continue;
}
if (ret == (int) sol.size() + 1) {
sol += b;
continue;
}
sol += c;
}
if ((int) sol.size() == n - 1) {
char a = posi[0];
char b = posi[1];
char c = posi[2];
if (press(sol + a) == n) {
sol += a;
} else {
if (press(sol + b) == n) {
sol += b;
} else {
sol += c;
}
}
}
return sol;
}
