use strict;

my @user = (1,3,5,7,9);

my %log = ( 1 => 'today',
            2 => 'today',
            3 => 'yesterday',
            4 => 'last week',
            5 => 'now' );

my %result;

foreach my $x (@user) {
  # Save the id ($x) in the result hash, save the location
  # of data as value, 'both' if $log{$x} exists, user if not
  $result{$x} = $log{$x} ? 'both' : 'user';
}

foreach my $y (keys %log) {
  # Save the id ($y) in the result hash, save the location
  # of data as value only if the id does not exist in result
  # hash yet
  $result{$y} = 'log' unless $result{$y};
}

foreach my $z (sort keys %result) {
  print "$z: $result{$z}\n";
}
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1: both
2: log
3: both
4: log
5: both
7: user
9: user
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first you'd get the values of the hash.


Inversely, it might be more effective to put the array into a hash.


@file_contents_array = <FH>;
%file_contents = map {$_ => 1} @file_contents_array;

# Now you can more easily compare
# %file_contents with your existing hash
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