The problem statement says:
New addresses will be added on a daily basis.

I assumed that to mean that the table will be emptied daily, and only new addresses would be added.

They said the table would be clean initially. (If the person putting forth the constraints can impose conditions, so can I).

With this assumption, no additional tracking is necessary.

             "I'm fairly sure if they took porn off the Internet, there'd only be one website left, and it'd be called 'Bring Back the Porn!'"
        -- Dr. Cox, Scrubs

In reply to Re^3: Please provide a hint for me to continue with the rest of my program by NetWallah
in thread Please provide a hint for me to continue with the rest of my program by pooyan

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