#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
char lookup[] = {'A','B','X','Y'};
//int press(std::string p);
string guess_sequence(int N) {
string p = "";
for(int i = 1; i <= N; i ++){
int tries = 0;
for(int j = 0; j < 4; j ++){
if(i >= 2 && p[0]==lookup[j]){continue;}
tries ++;
if(press(p+lookup[j]) == i){
p += lookup[j];
//printf("%d %s\n", i, p.c_str());
break;
}
}
}
return p;
}
/*
namespace {
constexpr int MAX_N = 2000;
constexpr int MAX_NUM_MOVES = 8000;
int N;
std::string S;
int num_moves;
void wrong_answer(const char *MSG) {
printf("Wrong Answer: %s\n", MSG);
exit(0);
}
} // namespace
int press(std::string p) {
if (++num_moves > MAX_NUM_MOVES) {
wrong_answer("too many moves");
}
int len = p.length();
if (len > 4 * N) {
wrong_answer("invalid press");
}
for (int i = 0; i < len; ++i) {
if (p[i] != 'A' && p[i] != 'B' && p[i] != 'X' && p[i] != 'Y') {
wrong_answer("invalid press");
}
}
int coins = 0;
for (int i = 0, j = 0; i < len; ++i) {
if (j < N && S[j] == p[i]) {
++j;
} else if (S[0] == p[i]) {
j = 1;
} else {
j = 0;
}
coins = std::max(coins, j);
}
return coins;
}
int main() {
char buffer[MAX_N + 1];
if (scanf("%s", buffer) != 1) {
fprintf(stderr, "Error while reading input\n");
exit(1);
}
S = buffer;
N = S.length();
num_moves = 0;
std::string answer = guess_sequence(N);
if (answer != S) {
wrong_answer("wrong guess");
exit(0);
}
printf("Accepted: %d\n", num_moves);
return 0;
}
*/
