CPP_Regex_02.cpp

#include<iostream>
#include<string>
#include<vector>
#include<regex>
using namespace std;

int main() {
	string str;
	while (true) {
		cin >> str;
        smatch m; //typedef std::match_results<string>

        //We can define two groups here to extract the user name and 
        //domain name
		regex e("([[:w:]]+)@([[:w:]]+)\.com");

		//search the string for regular expression e and save the 
        //results to m
		bool match = regex_search(str, m, e);

        cout << "match size: " << m.size() << endl;
        for(int i = 0; i < m.size(); ++i){
            //print out the matched results
            cout << "m[" << i <<"]: str() = " << m[i].str() <<endl;
        }
        //prefix is everything before the first matched character
        cout <<"m.prefix().str(): " << m.prefix().str() << endl;
        //suffic is everything after the last matched character
        cout <<"m.suffix().str(): " << m.suffix().str() <<endl;
	}
	return 0;
}