题解 | #数据分类处理#

import sys

in_i = [int(x) for x in input().split()[1:]]
in_r = map(int, input().split()[1:])
r = list(set(in_r))
r.sort()
out_dict = {}
toil = 0
for i in r:
    tem = []
    for x, y in enumerate(in_i):
        if str(i) in str(y):
            tem.append(x)
            tem.append(y)
    if tem:
        out_dict[i] = tem
        toil += 2 + len(tem)
out_list = []
out_list.append(toil)
for key, value in  out_dict.items():
    out_list.append(key)
    i_len = int(len(value) / 2)
    out_list.append(i_len)
    out_list.extend(value)
print(" ".join(map(str, out_list)))