Is :0c is required for defining multiple email address

Query :   # If I defined in procmailrc as follows

              :0
               * ^TOnilanjan(_at_)shrilcal(_dot_)virtualave(_dot_)net
                ! nilanjan

              :0
                * ^sales(_at_)srilcal(_dot_)virtualave(_dot_)net
                ! sales

                :0
                * ^infosys(_at_)shrilcal(_dot_)virtualave(_dot_)net
                ! infosys

1. Will it work properly or we have to give the
flag as :0c in all the blocks above . If so why?

2. Does the mail become delivered mail after the
first test occurs resulting in unmatched. or remain
as undelivered mail and go to the next blocks for
testing ?

Assumed each :0 described in rcfile as a block.

Regards

Nilanjan Sircar