Maybe I'm missing something here, but it seems these answers are unnecessarily complicated.

If you want to know how many elements are in an array, Perl gives that to you:

    my $elementCount = @myArray;
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The first three elements are [0], [1], and [2].
The last three are [-1], [-2], and [-3](counted from the end, so, backwards):

    for (my $currentElementNumber = 0; $currentElementNumber < 3; $cur
+rentElementNumber++)
    {
        my $currentElementValue = $myArray[$currentElementNumber];
        # Do stuff here
    }
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