Is there any way I can pass Account Ids in the below link for merging account using APEX?

This is the link for Account Merging two accounts.

p = new pagereference('https://cs8.salesforce.com/merge/accmergewizard.jsp?goNext=+Next+&cid=001L0000005T4bK&cid=001L0000005T4bo')

How can I pass two cids dynamically in the above URL?

When I tried it using two variables to pass I got this result

https://cs8.salesforce.com/merge/accmergewizard.jsp?cid=001L0000005T4bK&goNext=+Next+

 

 Appreciate any help on this.

 How can I

On the Field Update Detail page, what does 'Re-evaluate Workflow Rules after Field Change' do?