Korrekt input / konvertering

Kode 

#include <iostream>
#include <regexx.hh>

using namespace std;
using namespace regexx;

int main (int argc, char ** argv)
{
    Regexx regex;

    if (argc == 1) {
        cout << "Brug: " << argv[0] << " dato" << endl;
        return 0;
    }

    try {
        if (regex.exec(argv[1], "\\\\\\\\d\\\\\\\\d/\\\\\\\\d\\\\\\\\d/\\\\\\\\d\\\\\\\\d\\\\\\\\d\\\\\\\\d")) {
            cout << "Korrekt dato" << endl;
        } else {
            cout << "Der er fejl i datoen" << endl;
        }
    } catch (Regexx::CompileException & e) {
        cerr << e.message() << endl;
    }
    return 0;
}

Kode 

robert@debian:~$ g++ test.cpp -o test -lregexx robert@debian:~$ ./test
Brug: ./test dato
robert@debian:~$ ./test blar
Der er fejl i datoen
robert@debian:~$ ./test "10/05/1978"
Korrekt dato
robert@debian:~$

Kode 

#include <iostream>
#include <cstdlib>
#include <regexx.hh>

using namespace std;
using namespace regexx;

int main (int argc, char ** argv)
{
    Regexx regex;

    if (argc == 1) {
        cout << "Brug: " << argv[0] << " dato" << endl;
        return 0;
    }

    try {
        if (regex.exec(argv[1], "(\\\\\\\\d{1,2})/(\\\\\\\\d{1,2})/(\\\\\\\\d{2,4})")) {
            cout << "Korrekt dato format" << endl;
            int date = atoi(regex.match[0].atom[0].str().c_str());
            int month = atoi(regex.match[0].atom[1].str().c_str());
            int year = atoi(regex.match[0].atom[2].str().c_str());

            cout << "Dato: " << date << endl;
            cout << "Måned: " << month << endl;
            cout << "År: " << year << endl;
        } else {
            cout << "Der er fejl i datoen" << endl;
        }
    } catch (Regexx::CompileException & e) {
        cerr << e.message() << endl;
    }
    return 0;
}

Kode 

robert@debian:~$ ./test 1/7/1999
Korrekt dato format
Dato: 1
Måned: 7
År: 1999
robert@debian:~$ ./test 01/07/1999
Korrekt dato format
Dato: 1
Måned: 7
År: 1999
robert@debian:~$ ./test 1/07/99
Korrekt dato format
Dato: 1
Måned: 7
År: 99
robert@debian:~$

Kode 

#include <iostream>
#include <sstream>

using namespace std;

int main(int, char *argv[])
{
   stringstream SS(argv[1]);
   unsigned int Time, Minut, Sekund;
   char D1, D2;

   if(SS >> Time >> D1 >> Minut >> D2 >> Sekund && D1 == ':' && D2 == ':')
      cout << "Success: " << Time << " " << Minut << " " << Sekund << endl;
   else
      cout << "Failed " << endl;
}