xbee radio communication

May I ask for help ? I buy two xbee radios I want to build communication between the two modules and it can send or receive datas , nomatter it is point-to-point , point-to-multipoint or peer-to-peer topologies . So I configure the two modules as following . I use an usb cable to connect it with my pc
Then I configure the two module as following . After that I edit the codes , the one (named A) is :

void setup()
{
   Serial.begin(9600);
}
void loop()
{
   Serial.println(random(2,200));
   delay(1000);
}

and the other(named B) is :

void setup()
{
   Serial.begin(9600);
}

void loop()
{
  if(Serial.available())
 {
      Serial.println(Serial.read());
  }
}

In order to see datas , I open the Arduino IDE serial monitor . It shows nothing ,as follows:
why it is that ? I just don’t know how to configure the two modules and send or receive datas without AT command .How can I get that ?

Looks to me like the wrong modem type is selected (XB24-B). It should be XB24-ZB for regular XBee-ZB modules (f.k.a. Series 2). But we really would like to know the Digi part number of the model you are working with (e.g. XB24-Z7WIT-004), so add that to the additional information that is needed.

Did you read this comment from your other thread? Perhaps this is where your problems at.