Arduino & Ethernet Shield & RFID MFRC522

Hi. I want to make a project with an Arduino Mega, an Ethernet Shield and RFID MFRC522. I wrote this sketch but nothing works. I connected pin 3 to SDA and pin 5 to RST. The library is down here.
Ideas?

RFID.zip (5.81 KB)

RfidEthernetExample.zip (2.77 KB)

I connected pin 3 to SDA and pin 5 to RST.

Pin 3 of what? Pin 5 of what?

Which of those files are we supposed to look at? "Nothing works" is NOT correct. Something happens. What actually happens may not be what you expect. But, you need to tell us what happens and what you expect, so we can tell you why your expectations are wrong.

I followed this guide

and now RFID and Eth shield work, but SD do not.
How can i do?