What will be the output of the following C# code?

 class abc
 {
     public static void a()
     {
         console.writeline("first method");
     }
     public void b()
     {
         a();
         console.writeline("second method");
     }
     public void b(int i)
     {
         console.writeline(i);
         b();
     }
 }
 class program
 {
     static void main()
     {
         abc k = new abc();
         abc.a();
         k.b(20);
     }
 }