#!/usr/bin/python3
import sys
import os.path

if "__main__" == __name__:
    if not (len(sys.argv) == 3 or len(sys.argv) == 4):
        print("Usage : python {0} file1 file2 [ranknum]".format(sys.argv[0]))
        exit(1)

    if not os.path.isfile(sys.argv[1]) or not os.path.isfile(sys.argv[2]):
        print("check files :\nfile1 : {0}\nfile2 : {1}".format(sys.argv[1], sys.argv[2]))
        exit(1)

    rank1 = []
    rank2 = []

    if len(sys.argv) == 4 and sys.argv[3].isnumeric():
        rank = int(sys.argv[3])
    else:
        rank = 1000

    with open(sys.argv[1]) as f:
        for line in f:
            rank1.append(line[line.index('http'):].replace('\n', ''))

    with open(sys.argv[2]) as f:
        for line in f:
            rank2.append(line[line.index('http'):].replace('\n', ''))

    count = 0

    if rank <= len(rank1) and rank <= len(rank2):
        for url in rank1[:rank]:
            if url in rank2[:rank]:
                count += 1
    else:
        for url in rank1:
            if url in rank2:
                count += 1
    print(count)