my @array1 = (1, 2, 3);
my @array2 = (3, 4, 5);

my %union = ();
map { $union{$_}++ } (@array1, @array2);
my @array3 = keys %union;

[download]
Update: dragonchild is right. map is slower than a for loop. Use his code above, but you should still learn the wonderful world of map!

Update2:I like this one by danboo the best: @array3 = keys %{{ map {$_ =>1} @array1, @array2 }}; It uses map in a non-void context, does a simple assignment operation instead of the addition/auto-vivify, and is still quite readable. Am I wrong? Is there a more optimized solution?

In reply to Re: Arrays by joealba
in thread Comparing Two Arrays by Anonymous Monk

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