It does look to be the most efficient as you suspected.

The really fastest version -- which is only applicable if you no longer need the original array and can modify it in place, which is often the case in my work -- is: 

my $i = 0; $x[ $i ] -= $x[ ++$i ] while $i < $#x; --$#x;

[download]

But the saving comes from not allocating more memory; and all the algorithms would benefit from that.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". The enemy of (IT) success is complexity.
In the absence of evidence, opinion is indistinguishable from prejudice. Suck that fhit

In reply to Re^6: Abusing Map (Corrected second code block) by BrowserUk
in thread Abusing Map by writch

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