#include <bits/stdc++.h>
using namespace std;
char c[1000];
int a[1000];
int main() {
  int n;
  cin >> n;
  memset(c, 0, sizeof(c));
  memset(a, 0, sizeof(a));
  scanf("%s", c);
  for (int i = 0; c[i] != '\0'; i++) a[c[i]] = 1;
  int ans = 0;
  for (int i = 0; i <= 26; i++)
    if (a[i + 'a']) ans++;
  if (ans >= n) {
    printf("YES\n");
    for (int i = 0; c[i] != '\0';) {
      if (a[c[i]]) {
        a[c[i]] = 0;
        printf("%c", c[i]);
        i++;
        while ((!a[c[i]] || n == 1) && c[i] != '\0') {
          printf("%c", c[i]);
          i++;
        }
      }
      n--;
      cout << endl;
    }
  } else
    printf("NO\n");
  return 0;
}
