#include <bits/stdc++.h>
#include "combo.h"
using namespace std;
string guess_sequence(int N){
string s, s1, s2, s3;
int k = press("AB");
if(k == 2){
s += "A";
} else if(k == 1){
k = press("A");
if(k) s += "A";
else s += "B";
} else{
k = press("X");
if(k == 2) s += "X";
else s += "Y";
}
int lst = 1;
if(s == "Y"){
s1 = "A";
s2 = "B";
s3 = "X";
} else if(s == "X"){
s1 = "A";
s2 = "B";
s3 = "Y";
} else if(s == "B"){
s1 = "A";
s2 = "X";
s3 = "Y";
} else{
s1 = "B";
s2 = "X";
s3 = "Y";
}
for(int i = 1; i < N-1; i++){
string a, b, c, d, e;
a = s; a += s1; a += s1; b = s; b+= s1; b += s2; c = s; c += s1; c += s3; d = s; d += s2;
e += a; e += b; e += c; e += d;
int tp = press(e);
if(tp == lst+1){
s += s2;
} else if(tp == lst){
s += s3;
} else {
s += s1;
}
lst++;
}
if(lst == N-1){
string st = s+s1;
int t = press(st);
if(t == N) s = st;
else{
st = s + s2;
t = press(st);
if(t == N) s = st; else s += s3;
}
}
return s;
}
