using System;
class SystemInformation
{
static void Main(string[] args)
{
string machineName = Environment.MachineName;
string domainName = Environment.UserDomainName;
string userName = Environment.UserName;
Console.WriteLine("Machine name: {0}", machineName);
Console.WriteLine("Domain name: {0}", domainName);
Console.WriteLine("User name: {0}", userName);
}
}