Hi, I am new to perl. I am trying to write a simple script that will pass through an array subtracting the value of the an element from that of the next and so on. Reporting each answer on a new line. One of my many problems is that I am not sure how to refer to the n+1 element in an array: Here what I have so far: 

#!/usr/bin/perl
use warnings;

open(FILE, "filename.txt") or die("Unable to open file");

@List = <FILE>;

close(FILE);

foreach $line (@List)
  {
        print ($line+1) - $line);
        print "\n";
}

[download]
Any help would be much appreciated! Thanks, Art

In reply to subtractionn in an array by brachysclereid

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