Remove similar elements in both the array

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Monks,

I have two arrays @a and @b, i want to remove the similar elements in both arrays and retain the dissimilar elements.

@a = (2, 6.5 ,4, 3, 2, 7.5, 4.0);
@b = (2, 6.52 ,4.5, 7.05, 2.0, 4.1, 3);
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The output i need is:

@a = (6.5, 4, 7.5, 4.0)
@b = (6.52, 4.5, 7.05, 2.0, 4.1)
[download]

How can we attain this.

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Re: Remove similar elements in both the array by data64 (Chaplain) on Mar 08, 2005 at 05:07 UTC
This is covered in the Perl FAQ. See How do I compute the difference of two arrays?	[reply]
Re^2: Remove similar elements in both the array by DrHyde (Prior) on Mar 08, 2005 at 10:32 UTC
It's also in the Q&A section of this august forum, at How can I find the union/difference/intersection of two arrays?.	[reply]
Re: Remove similar elements in both the array by tilly (Archbishop) on Mar 08, 2005 at 04:38 UTC
`my %in_a; my %in_b; undef @in_a{@a}; undef @in_b{@b}; @a = grep {not exists $in_b{$_}} @a; @b = grep {not exists $in_a{$_}} @b;` [download] Update: I guess that I do need the braces after all, as davis noted I didn't run the code. Sorry.	[reply] [d/l]
Re^2: Remove similar elements in both the array by davis (Vicar) on Mar 08, 2005 at 09:58 UTC
`@a = grep not exists $in_b{$_}, @a; @b = grep not exists $in_a{$_}, @b;` [download] According to my perl: `Not enough arguments for grep at j.pl line 14, near "@a;" Execution of j.pl aborted due to compilation errors.` [download] I think you want: `#!/usr/bin/perl use warnings; use strict; use Data::Dumper; my @a = (2, 6.5 ,4, 3, 2, 7.5, 4.0); my @b = (2, 6.52 ,4.5, 7.05, 2.0, 4.1, 3); my %in_a; my %in_b; undef @in_a{@a}; undef @in_b{@b}; @a = grep {not exists $in_b{$_}} @a; @b = grep {not exists $in_a{$_}} @b; print Dumper(\@a); print Dumper(\@b);` [download] davis It wasn't easy to juggle a pregnant wife and a troubled child, but somehow I managed to fit in eight hours of TV a day.	[reply] [d/l] [select]