#include "combo.h"
#include <bits/stdc++.h>
using namespace std;
string c[4] = {"A", "B", "X", "Y"};
string guess_sequence(int N) {
string s;
int co, a, b, d;
a = b = d = 1;
co = press(c[0] + c[1]);
if(co > 0) {
co = press(c[0]);
if(co > 0) s = c[0];
else s = c[1];
}
else {
co = press(c[2]);
if(co > 0) s = c[2];
else s = c[3];
}
for(int i = 0; i < 4; i++) {
if(s == c[i]) {
a = (i+1)%4;
b = (i+2)%4;
d = (i+3)%4;
}
}
for(int i = 1; i < N-1; i++) {
string s1 = s + c[a] + c[a];
string s2 = s + c[a] + c[b];
string s3 = s + c[a] + c[d];
string s4 = s + c[b];
co = press(s1 + s2 + s3 + s4);
if(co == i+2) s += c[a];
else if(co == i+1) s += c[b];
else s += c[d];
}
co = press(s + c[a]);
if(co == N) s += c[a];
else {
co = press(s + c[b]);
if(co == N) s += c[b];
else s += c[d];
}
return s;
}
