Hi again,

I would like to seek your help in optimizing a double loop which is in the heart of my program. I really need it to be as efficient as possible to cut on running times, since it is called many times.

The idea is this. I have a large array @arr of size up to 10^6. I then get "ranges" in this array e.g. {FROM=>25000 TO=>40000} and I need to ++ all the cells in the range. What I do now is something like: 

my @arr= (0) x $length;
while ( ... get range to process ...) {
 for (my $i=$range->{FROM}; $i<$range->{TO}; ++i) {
  $arr[$i]++;
 }
}

[download]

Is there anything I can do to optimize this process? Assume "get range to process" is already optimized.

Thanks!

In reply to Optimizing a double loop by roibrodo

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