int _tmain(int argc, _TCHAR* argv[])
{
    string email1S = "abc 31432";
    cmatch results;
    regex mcn("([[:digit:]]+)");
    string::const_iterator curPosition = email1S.begin();

    if (regex_search(curPosition, email1S.cend(), results, mcn))
    {
        cout << "We have a match" << endl;
        cout << results[1].str() << endl;
    }
    curPosition += results[0].length();
    cin.get();
    return 0;
}