#include <bits/stdc++.h>
using namespace std;
int main() {
  int k, u = 0, i;
  vector<char> m;
  vector<int> pos;
  cin >> k;
  string ch;
  cin >> ch;
  if (k == 1) {
    cout << "YES\n" << ch << endl;
    return 0;
  } else if (k > ch.size()) {
    cout << "NO" << endl;
    return 0;
  }
  m.push_back(ch[0]);
  pos.push_back(0);
  u++;
  for (int i = 1; i < ch.size(); i++) {
    if (find(m.begin(), m.end(), ch[i]) == m.end()) {
      m.push_back(ch[i]);
      pos.push_back(i);
      u++;
    }
    if (u >= k) break;
  }
  if (u < k)
    cout << "NO" << endl;
  else {
    cout << "YES\n";
    int y = pos.size();
    for (i = 0; i < k - 1; i++) {
      for (int j = pos[i]; j < pos[i + 1]; j++) {
        cout << ch[j];
      }
      cout << endl;
    }
    for (int j = pos[k - 1]; j < ch.size(); j++) {
      cout << ch[j];
    }
    cout << endl;
  }
  return 0;
}
