Hi Monks,

In my journey to enlightenment I am looking for efficiency.

My problem is I have two arrays and I want to compare them and list those elements that are common to both and those that are unique.

e.g. 

my @one = [1,2,3,4];
my @two = [2,4,6,8];

sub cf{...}

common = [2,4];
unique_one = [1,3];
unique_two = [6,8];

[download]
Now I am sure that this is a common problem and I know that a set of nested for loops would work - comparing each element in turn. But there must be a better way. Is it time for my understanding of map to grow beyond the "little black book" description?

Thanks

A.A.

In reply to Efficient Comparison of Array elements by aging acolyte

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