31.
What will be the result of compiling and running the given code?
class A{
      int b=10;
      private A(){
            this.b=7;
      }
      int f(){
            return b;
      }
}
class B extends A{
      int b;
}
public class Test{
      public static void main(String[] args){
            A a = new B();
            System.out.println(a.f());
      }
}