static void Main(string[] args)
{
ISet <int> f1 = new SortedSet <int>();
ISet <int> f2 = f1;
Console.WriteLine($"F1 : {f1.GetHashCode()} , type :{f1.GetType()}");
Console.WriteLine($"F2 : {f2.GetHashCode()} , type :{f2.GetType()}");
Person p1 = new Person(iage: 21, iname: "Tom");
Console.WriteLine($"p1 : {p1.GetHashCode()} , type :{p1.GetType()}");
ChangeName(p1);
Console.WriteLine($"Name : {p1.name} ");
Expression <Func <int, int, bool> > f = (s1, s2) => s1 < s2;
Console.WriteLine(f.Body);
object[] vals = { "abc", "xyz", "lmn" };
IEnumerable <string> val1 = vals.OfType <string>();
val1.Where(s => s.Contains("a"));
}
public static void ChangeName(Person iP)
{
Console.WriteLine($"p1 : {iP.GetHashCode()} , type :{iP.GetType()}");
iP.name = "Jon";
}