static void Main(string[] args)
{
Parent a = new Parent("a");
a.PMethod();
child b = new child("b");
b.PMethod();
b.CMethod();
}
static void Main(string[] args)
{
parent p = new parent();
p.showVehicle();
child c = new child();
c.showVehicle();
c.show();
Console.WriteLine("Single Inheritance");
subchild s = new subchild();
s.showVehicle();
s.show();
s.sub();
}