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Dear Perl experts,

Seeking advice here. I am a newbie with Perl and looking for input on the quickest way to perform a difference between two arrays.

The two arrays are going to be large, they could be holding between 6,000 to 8,000 elements, these elements will hold unique data. Due to the size of these arrays, the diff will need to be fast and not intensive on the CPU.

Here is the code I have used which does carry out its function correctly which is to find the items in @arr_1 that are not present in @arr_2.

The data in each of the arrays is unique and is an INT data type

My question is whether there is a faster way that is less intensive on the CPU?

    my %diff3;    
    @diff3{ @arr_1 } = @arr_1;
    delete @diff3{  @arr_2};
    @diff = (keys %diff3);
[download]

Thank you in advance, once I get up to speed on Perl, I am looking forward to paying it back.

In reply to Best method to diff very large array efficiently by newbieperlperson

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