#include <bits/stdc++.h>
char q[101];
int di[101];
int a[27];
int main() {
  int k, len, i, d = 1;
  scanf("%d", &k);
  scanf("%s", q);
  len = strlen(q);
  di[0] = 1;
  a[q[0] - 96] = 1;
  for (i = 1; i < len; i++) {
    if (k == d) break;
    if (a[q[i] - 96] == 0) {
      di[i] = 1;
      a[q[i] - 96] = 1;
      d++;
    }
  }
  if (k != d)
    printf("NO\n");
  else {
    printf("YES");
    for (i = 0; i < len; i++) {
      if (di[i] == 1) printf("\n");
      printf("%c", q[i]);
    }
  }
  return 0;
}
