题解 | #数据分类处理#

I_input = list(map(int,input().split()))
I_num,I = I_input[0],I_input[1:]
R_input = list(map(int,input().split()))
R_num,R = R_input[0],list(sorted(set(R_input[1:])))
result = {}
for i in range(len(R)):
    result[R[i]] = []
for i in R:
    for j,index in zip(I,range(len(I))):
        if str(i) in str(j):
            result[i].append([index,j])
result_str = ''
result_len = 0
for i in range(len(R)):
    if len(result[R[i]])!=0:
        result[R[i]] = [len(result[R[i]])]+[element for row in result[R[i]] for element in row]
        result_len += len(result[R[i]]) +1
        result_str += str(R[i])+' ' + ' '.join(map(str, result[R[i]])) + ' '
# print(I,R)
# print(result)
print(result_len,result_str)