#include<bits/stdc++.h>
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define vi vector<int>
#define fi first
#define se second
#define all(x) (x).begin(),(x).end()
using namespace std;
int m;
string suf,pref;
int query(string str);
string guess(int n, int s) {
string pref,P;
for (int i = 1; i <= n; i++) {
int len = suf.size();
char LAST = ((int)pref.size() ? pref.back() : 'a');
int cur = len;
for (int z = 1; z + len <= n; z++) {
bool flag = 0;
for (char c = 'a'; c < 'a' + s; c++) {
P = pref + c;
P += suf;
int F = query(P);
if (F > cur) {
LAST = c;
pref += c;
cur = F;
flag = 1;
break;
}
}
if (flag == 0) break;
}
reverse(all(suf));
suf+=LAST;
reverse(all(suf));
if (pref.size())
pref.pop_back();
}
return suf;
}
/*
main() {
ios::sync_with_stdio(0);
cin.tie(0);
}*/
