a = input().split()
a_num = int(a.pop(0))
b = input().split()
b_num = int(b.pop(0))


b = [int(i) for i in set(b)]
b.sort()
b = [str(i) for i in b]


res=[]
for x in b:
    cnt = 0
    total = len(res)
    for i in range(len(a)):
        if x in a[i]:
            cnt +=1
            res.append(i)
            res.append(a[i])
    if cnt!=0:
        res.insert(total,cnt)
        res.insert(total,x)
    
total = len(res)
res.insert(0,total)

print(' '.join(str(i) for i in res))