#!/usr/bin/python

# P2PU - Python Programming 101 - Chapter 10 - Regular Expressions
# Python for Informatics - Chapter 11 - Regular Expressions
# Exercise 11.1

import re

def grep(regex, fhand):
    matches = 0
    for line in fhand:
        line = line.rstrip()
        if re.search(regex, line): matches += 1
    return matches

regex = raw_input('Enter a regular expression: ')
fname = 'mbox.txt'
fhand = open(fname)

print "%s had %d lines that matched %s" % (fname, grep(regex, fhand), regex)