#include <bits/stdc++.h>
using namespace std;
const int maxn = 100 + 10;
int a[maxn], chk[maxn];
string str;
int main() {
  int n, k = 0;
  cin >> n >> str;
  if (str.size() < n) {
    cout << "NO";
    return 0;
  }
  for (int i = 0; i < str.size(); i++) {
    if (a[str[i] - '0'] == 0) k++;
    a[str[i] - '0'] = 1;
  }
  if (k < n) {
    cout << "NO";
    return 0;
  }
  cout << "YES" << endl;
  for (int i = 0; i < str.size(); i++) {
    if (chk[str[i] - '0'] == 0 && n > 1 && i != 0) {
      cout << endl;
      n--;
    }
    cout << str[i];
    chk[str[i] - '0'] = 1;
  }
  return 0;
}
