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.");
}
}
}