You are given a string *q*. A sequence of *k* strings *s*<sub class="lower-index">1</sub>, *s*<sub class="lower-index">2</sub>, ..., *s*<sub class="lower-index">*k*</sub> is called beautiful, if the concatenation of these strings is string *q* (formally, *s*<sub class="lower-index">1</sub> + *s*<sub class="lower-index">2</sub> + ... + *s*<sub class="lower-index">*k*</sub> = *q*) and the first characters of these strings are distinct.

Find any beautiful sequence of strings or determine that the beautiful sequence doesn't exist.
The first line contains a positive integer *k* (1 ≤ *k* ≤ 26) — the number of strings that should be in a beautiful sequence. 

The second line contains string *q*, consisting of lowercase Latin letters. The length of the string is within range from 1 to 100, inclusive.
# https://codeforces.com/problemset/problem/544/A

import fileinput
import sys
from typing import List

k: int
string: str
for i, line in enumerate(fileinput.input()):
    if i == 0:
        k = int(line[:-1])
    if i == 1:
        string = line[:-1]
        break

chars = set(char for char in string)

if len(chars) < k:
    print('NO')
    sys.exit(0)

print('YES')
last_char: str = string[0]
sub_start, sub_end, parts = 0, 0, 0
for i, char in enumerate(string):
    if char in chars:
        chars.remove(char)
        if i > 0:
            print(string[sub_start:sub_end])
        sub_start, sub_end = i, i + 1
        parts += 1
        if parts >= k:
            print(string[sub_start:])
            break
    else:
        sub_end += 1
