import sys
res = sys.stdin.readlines()[0].split()
# 字符串的个数
n = int(res[0])
# 字符串的内容
string2n = res[1:-2]
# 字符串x
xstr = res[-2]
k = int(res[-1].replace('\n',''))

target_data = []
for i in string2n:
    if sorted(i)==sorted(xstr) and i != xstr:
        target_data.append(i)

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