import sys

input_str = sys.stdin.readline().strip().split()
n = int(input_str[0])
string = input_str[1 : 1 + n]
x = input_str[1 + n]
k = int(input_str[-1])

res = []
for s in string:
    if s != x and ''.join(sorted(s)) == ''.join(sorted(x)):
        res.append(s)

res.sort()

print(len(res))
if len(res) >= k:
    print(res[k - 1])