An array element is referenced using SQUARE brackets and a Dollar sigil.

You should be using 

    print "difference is " . $array[$counter] - $array[$counter - 1];

[download]
Your second "foreach" is not necessary.
It can be replaced by: 
      print "difference is " . $array[$#array] - $array[-2] , "\n";

[download]

See correction below

                "Imaginary friends are a sign of a mental disorder if they cause distress, including antisocial behavior. Religion frequently meets that description"

In reply to Re: simplish script (I think) by NetWallah
in thread simplish script (I think) by notoriousrab430

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