#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int k;
string s;
cin >> k >> s;
vector<pair<char,int>>vec;
for (int i = 0; i < (int)s.size(); i++) {
if (vec.empty() || vec.back().fi != s[i]) vec.push_back({s[i],1});
else if (vec.back().fi == s[i]) vec.back().se++;
if (vec.back().se == k) vec.pop_back();
}
if (vec.size() == 0) cout << 0;
for (auto x: vec)
for (int i = 1; i <= x.se; i++) cout << x.fi;
cout << "\n";
}
