#include "combo.h"
#include "assert.h"
std::string guess_sequence(int N) {
std::string S = "";
char buttons[] = {'A', 'B', 'X', 'Y'};
std::string p = "";
char first_character;
// guess the first character
p = "AB";
if (press(p) > 0) {
p = "A";
if (press(p) > 0) {
first_character = 'A';
}
else {
first_character = 'B';
std::swap(buttons[0], buttons[1]);
}
}
else {
p = "X";
if (press(p) > 0) {
first_character = 'X';
std::swap(buttons[0], buttons[2]);
}
else {
first_character = 'Y';
std::swap(buttons[0], buttons[3]);
}
}
if (N == 1) {
return std::string(1, first_character);
}
std::string prefix(1, first_character);
for (int i = 2; i <= N - 1; i++) {
std::string query = prefix + buttons[1] + buttons[1] + prefix + buttons[1] + buttons[2] + prefix + buttons[1] + buttons[3] + prefix + buttons[2];
int curr_coin = press(query);
if (curr_coin == i + 1) {
prefix += buttons[1];
}
else if (curr_coin == i) {
prefix += buttons[2];
}
else {
prefix += buttons[3];
}
}
// guess the last character
bool found = false;
for (int i = 1; i <= 2; i++) {
S = prefix + buttons[i];
if (press(S) == N) {
found = true;
break;
}
}
if (!found) {
S = prefix + buttons[3];
}
return S;
}
