using System; delegate void D(int x); class A { public static void A1(int i) { Console.WriteLine("A1: {0}", i); } public void A2(int i) { Console.WriteLine("A2: {0}", i); } } class T { public static void Main() { D x = new D(A.A1); x(1); A t = new A(); D y = new D(t.A2); y(2); D z = new D(y); z(3); D q = x + y; q(11); q += z; q(12); q -= x; q(13); D r = new D(q - y + x); r(14); } }