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.
def setofstrings():
    k= int(input())
    q= input()
    
    qset= set([i for i in q])
    if len(qset)< k:
        print("NO")
        return
    firsts= []
    print("YES")
    if k== 1:
        print(q)
        return
    last= 0
    firsts.append(q[0])
    for i in range(len(q)):
        if q[i] not in firsts:
            firsts.append(q[i])
            print(q[last:i])
            last= i
            k-= 1
            if k== 1:
                print(q[last:])
                return
            
setofstrings()