If Method calls are dynamically binded then why the Compiler complains The method xyz is undefined for the type xxx

If Method calls are dynamically binded then why the Compiler complains The
method xyz is undefined for the type xxx

If Method calls are dynamically binded then why the Compiler complains
The method run() is undefined for the type B
Why is compiler checking for the presence of method run in Class b
Here is the code
import java.lang.*;
public class Program
{
public static void main(String [] args)
{
B a = new A();
a.run();//compiler complains at this line.
a.p(10);
a.p(10.0);
}
}
class B {
public void p(int i)
{
System.out.println(i*2);
}
}
class A extends B{
public void p(int i)
{
System.out.println(i);
}
public void run(){
}
}