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How do I pick anything that is in array A that is NOT in array B

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Contributed by Anonymous Monk on Jun 30, 2000 at 11:56 UTC
Q&A  > arrays


Answer: How do I pick anything that is in array A that is NOT in array B
contributed by QandAEditors

The lingo for your desired operation is the difference of two arrays. This has already been answerd in How can I find the union/difference/intersection of two arrays?. Here's another solution which doesn't use a set hash:

@a_minus_b = grep { my $a = $_; not grep { $a eq $_ } @b } @a;
Answer: How do I pick anything that is in array A that is NOT in array B
contributed by gansi

use strict; my @A = (2..5); my @B = (4..7); my @A_not_B; foreach my $data ( @A ) { push @A_not_B, $data unless grep { $_ eq $data } @B; } print "FINAL :: @A_not_B \n";

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