I have a database that keeps routing paths to a destination

As such :
   
    Path  network  updatenumber 
     33      1          1
      4      1          1
     42      1          1
     34      1          1
     
     33      1          2
     42      1          2
     34      1          2

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So that is an example of a database whereby to reach a particular network in the example (1) you need to traverse through 33 -> 4 -> 42 -> 39, but as time goes on there are updates to the route. So, what i am trying to archive is to see the numbers in a path that appear and disappear often. Which is why i am comparing the first updated route, to the second updated route. With the difference, i will store in a separate table. If a value already exist on that table, i will just increment it.So logically the highest value on that table will be a device which is troubled.Because it keeps appearing and disappearing. In my example database above, 4 is a difference between both paths. So i will store that somewhere etc. From my question i already loaded this database values into the hash. I was just stuck at doing the previous->next logic.

In reply to Re^4: compare previous and present hash key values by undisputed
in thread compare previous and present hash key values by undisputed

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