Oh wise gurus. I humbly solicit your assistance in solving this problem.

I'm parsing some mail logs to check on some mail rejections. The issue that I'm not exactly sure how to proceed with is the data that I get from the logs.

Of course each sender could be sending to multiple recipients, so a simple hash won't do the trick I don't think. I'm not sure what the best approach is. A HoH, or a HoA. What I'm hoping to end up with a report something along the lines of the following. 

recipient1
  sender1
  sender2
  sender3
  ...
  ...
recipient2
  sender1
  sender2
  sender3
  ...
  ...

[download]
My thoughts are a HoA is the proper way to proceed. But I want to confirm my approach is correct before proceeding. Perhaps there is a better way?

Thanks,
Mike

Update: Thanks davido. I think my needs are simple. This is a small system. Very few users, lots of senders.

Update II: Thanks wfsp. I could complicate this greatly by doing something like the following, but that is really beyond the scope of what I'm trying to do at the moment. What I'm really trying to prove is the rejects are all valid. So I will be showing this data to the powers that be and let them see if any 'valid' mail is being rejected. 

recipient1
  sender1 -- reject reason
  sender2 -- reject reason
  sender3 -- reject reason
  ...
  ...
recipient2
  sender1 -- reject reason
  sender2 -- reject reason
  sender3 -- reject reason
  ...
  ...

[download]

In reply to HoH, HoA, or something else? by cajun

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