Your best place to find 2013 past papers of computer science 12th class from bise rawalpindi board. These old up to date papers can be downloaded or viewed online.
Computer Science Past Papers 2013 Rawalpindi Board
2013 Computer science Past Papers 9th Class BISE Rawalpindi Board Analysis
Campus.pk gives you unique insight into each past paper about what are the top chapters and topics.
Computer-science Past Papers 9th Class BISE Rawalpindi Board