题解 | #查找兄弟单词#

s = input().split()
word, k = s[-2], int(s[-1])
lst = []
for i in s[1:-2]:
    if i != word and len(i) == len(word):
        letters = list(word)
        for j in range(len(i)):
            if i[j] in letters:
                letters.remove(i[j]) 
            else:
                continue
        if len(letters) == 0:
            lst.append(i)
new = sorted(lst)
print(len(lst))
if 0 <= k <= len(lst):
    print(new[k-1])