import sys
while True:
    try:
        I = input().strip().split()[1:]
        s_r = input().strip().split()
        #先转成数值排序
        R = sorted(list(map(int, set(s_r[1:]))))
        #再换回字符串
        R = list(map(str,R))
#         print(I)
#         print(R)
        Res = []
        for c in R:
            find = []
            for index in range(len(I)):
                if c in I[index]:
                    find.append(index)
                    find.append(I[index])
            if len(find) > 0:
                Res.append(c)
                Res.append(len(find) // 2)
                Res = Res + find
        Res.insert(0, len(Res))
        print(" ".join(map(str,Res)))

    except:
#         print(sys.exc_info())
        break