Hi G0G0

Why do you need the @array? You could improve the required memory by changing 

my @array = (1..1000000000);
foreach (@array) {

[download]
to 
foreach (1..1000000000) {

[download]
(The first solution gives an "out of memory" on my system, the later runs in 50 seconds with an empty loop).

Inside the loop, you can probably save some time by reversing only once, and storing the intermediate result in a temporary variable. And based on the size of the current number, you could determine which of the substr-lines is relevant and skip the others...

HTH, Rata

In reply to Re: Perl script performance help by Ratazong
in thread Perl script performance help by G0G0

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