Re^3: comparing arrays

it doesn't matter which array the values are removed from.

In that case, it is very simple. You iterate over one array and rebuild it. If a value shows up in the second array, you just ignore it as you are rebuilding. Use a hash to store the values so that lookup is fast...

my @array1 = (1, 2, 3, 4, 5); 
my @array2 = (2, 4, 6, 8, 10); 
my %hash = map {$_=>1} @array2; 
@array1 = grep { not exists $hash{$_} } @array1;
print "@array1\n";
[download]

-sauoq
"My two cents aren't worth a dime.";

Comment on Re^3: comparing arrays Download Code

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Re^4: comparing arrays by Animator (Hermit) on Dec 16, 2004 at 15:16 UTC
A hash slice would (I guess) be more efficient (insted of the map-statement). `my %hash; @hash{@array2};` [download] This code will set for all the elements in @array2 the value in the hash to undef. And later on you can see if it exists by using the exists (or not exists) function (as done in your code).	[reply] [d/l]