static void Main(string[] args)
{
//C1 c1 = new C1();
//string r = c1.Data(5, "ALi");
//WriteLine(r);
//............
//C1 c1 = new C1();
//WriteLine(c1.Data(4, "Bilal"));
//......
IF1 f1 = new C1();
WriteLine(f1.Data(5, "Bilal"));
IF2 f2 = new C1();
WriteLine(f2.Data(10, "Khalil"));
ReadKey();
}