in reply to out of memory!

Intriguing. You use $i here: for ($i=0;$i<=(scalar(@blocks));$i++)

But then use $index here: if($blocks[$index]=~m/^\d/) ?

i have successfully executed scripts larger than this one,

It isn't the size of the script that counts; it is the size of the data.

And as you haven't shown us how you are populating @blocks; nor told us how big that array is, there is nothing we can to to help you.

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