Re^6: Abusing Map (Corrected second code block)

[BrowserUk]

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;

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