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