using System;
using System.Net.NetworkInformation;

class MainClass {
    static void Main() {
        if (NetworkInterface.GetIsNetworkAvailable()) {
            NetworkInterface[] interfaces = NetworkInterface.GetAllNetworkInterfaces();
            foreach (NetworkInterface ni in interfaces) {
                Console.WriteLine("     Physical Address: {0}", ni.GetPhysicalAddress().ToString());
            }
        } else {
            Console.WriteLine("No network available.");
        }
    }
}