Hello mimiandi,

While I agree that your OP needs clarification and supplemental code, here is a simple method using grep to gather keys that differ.

#!/usr/bin/perl

use strict;
use warnings;

my %file1 = ( samp1 => 'stuff',
              samp2 => 'data',
              samp3 => 'info', 
              samp4 => 'foo',
              samp5 => 'bar',
              blah  => 'blah',
              brood => 'other' );  

my %file2 = ( samp1 => 'stuff',
              samp2 => 'diff',
              samp3 => 'blah',
              samp4 => 'foo',
              junk  => 'stuff',
              trash => 'other',
              samp5 => 'bar' );

my (@diff1, @diff2);

push @diff1, grep !$file2{$_}, keys %file1;
push @diff2, grep !$file1{$_}, keys %file2;
[download]

Depending on the complexity of your data, you may want to have a look at Data::Compare. I believe Test::More also offers some tools for comparing data structures.

Post some code or at least some sample input data and I'm sure you'll rope some better answers.

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