ex17_23.cpp

/***************************************************************************
*  @file       main.cpp
*  @author     Queequeg
*  @date       26  Nov 2014
*  @remark     This code is for the exercises from C++ Primer 5th Edition
*  @note
***************************************************************************/
//
// Exercise 17.23


#include <iostream>
using std::cout;
using std::cin;
using std::endl;

#include<string>
using std::string;

#include <regex>
using std::regex;
using std::sregex_iterator;
using std::smatch;

bool valid(const smatch& m);

int main()
{
	string zipcode =
		"(\\d{5})([-])?(\\d{4})?\\b";
	regex r(zipcode);
	smatch m;
	string s;
	
	while (getline(cin, s))
	{

		//! for each matching zipcode number
		for (sregex_iterator it(s.begin(), s.end(), r), end_it;
			it != end_it; ++it)
		{
			//! check whether the number's formatting is valid
			if (valid(*it))
				cout << "valid zipcode number: " << it->str() << endl;
			else
				cout << "invalid zipcode number: " << s << endl;
		}

	}
	return 0;
}

bool valid(const smatch& m)
{
	
	if ((m[2].matched)&&(!m[3].matched))
		return false;
	else
		return true;
}