#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const int maxn = 2e6 + 10;
char a[1000];
int main() {
  map<char, int> mmp;
  int k;
  scanf("%d %s", &k, a);
  int len = strlen(a);
  int cur = 0;
  int d[1000];
  if (k == 1) {
    printf("YES\n");
    printf("%s", a);
  } else if (len < k)
    printf("NO\n");
  else {
    for (int i = 0; i < len; i++) {
      if (mmp[a[i]] == 0) {
        mmp[a[i]] = 1;
        d[cur++] = i;
      }
      if (cur == k) break;
    }
    if (cur != k)
      printf("NO\n");
    else {
      printf("YES\n");
      int be = d[0];
      for (int i = 1; i < cur; i++) {
        for (int j = be; j < d[i]; j++) printf("%c", a[j]);
        printf("\n");
        be = d[i];
      }
      for (int i = be; i < len; i++) printf("%c", a[i]);
      printf("\n");
    }
  }
  return 0;
}
