#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
typedef long long ll;
using namespace __gnu_pbds;
using namespace std;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
int query(string str);
int N;
void cut_first(string &s) {
reverse(s.begin(), s.end());
s.pop_back();
reverse(s.begin(), s.end());
}
string Merge(string s1, string s2) { // Not mine just for testing what part is wrong
string cur=s1; int idx=0;
for(char x:s2){
while(true){
string nwcur="";
for(int k=0; k<idx; k++)nwcur+=cur[k];
nwcur+=x;
for(int k=idx; k<(int)cur.size(); k++)nwcur+=cur[k];
if(query(nwcur)==nwcur.size()){
cur=nwcur; idx++; break;
}else idx++;
}
}
return cur;
}
string MergeSort(vector<string> t) {
if(t.size()==0) return "";
if(t.size()==1) return t[0];
vector<string> t1, t2;
int n =t.size();
for(int i=0; i<n/2; ++i) t1.push_back(t[i]);
for(int i=n/2; i<n; ++i) t2.push_back(t[i]);
return Merge(MergeSort(t1),MergeSort(t2));
}
string pwt(char c, int x) {
string s = "";
for(int i=0; i<x; ++i) s.push_back(c);
return s;
}
string guess(int n, int S) {
N=n;
string alph = "abcdefghijklmnopqrstuvwxyz";
vector<string> tab;
for(int i=0; i<S; ++i) {
tab.push_back(pwt(alph[i], query(pwt(alph[i],n))));
}
return MergeSort(tab);
}
