Hello, I have the following perl script which compares words in the 2nd field of two csv files, and if 5 or more words match then it prints both line together as a positive match.

#!/bin/perl                                                           
+                                             
                                                                      
+                                             
my @csv2 = ();                                                        
+                                             
open CSV2, "<csv2" or die;                                            
+                                             
@csv2=<CSV2>;                                                         
+                                             
close CSV2;                                                           
+                                             
                                                                      
+                                             
my %csv2hash = ();                                                    
+                                             
for (@csv2) {                                                         
+                                             
  chomp;                                                              
+                                             
  my ($title) = $_ =~ /^.+?,\s*([^,]+?),/; #/ match the title         
+                                             
  $csv2hash{$_} = $title;                                             
+                                             
}                                                                     
+                                             
                                                                      
+                                             
open CSV1, "<csv1" or die;                                            
+                                             
while (<CSV1>) {                                                      
+                                             
  chomp;                                                              
+                                             
  my ($title) = $_ =~ /^.+?,\s*([^,]+?),/; #/ match the title         
+                                             
    my %words;                                                        
+                                             
    $words{$_}++ for split /\s+/, $title;    #/ get words             
+                                             
    ## Collect unique words                                           
+                                             
    my @titlewords = keys(%words);                                    
+                                             
  my @new;                          #add exception words which shouldn
+'t be matched                                
  foreach my $t (@titlewords){                                        
+                                             
        push(@new, $t) if $t !~ /^(rare|vol|volume|issue|double|magazi
+ne|mag)$/i;                                  
  }                                                                   
+                                             
  @titlewords = @new;                                                 
+                                             
  my $desired = 5;                                                    
+                                             
  my $matched = 0;                                                    
+                                             
  foreach my $csv2 (keys %csv2hash) {                                 
+                                             
    my $count = 0;                                                    
+                                             
    my $value = $csv2hash{$csv2};                                     
+                                             
    foreach my $word (@titlewords) {                                  
+                                             
            my @matches   = ( $value=~/\b$word\b/ig );                
+                                             
            my $numIncsv2 = scalar(@matches);                         
+                                             
            @matches      = ( $title=~/\b$word\b/ig );                
+                                             
            my $numIncsv1 = scalar(@matches);                         
+                                             
            ++$count if $value =~ /\b$word\b/i;                       
+                                             
            if ($count >= $desired || ($numIncsv1 >= $desired && $numI
+ncsv2 >= $desired)) {                        
                $count = $desired+1;                                  
+                                             
                last;                                                 
+                                             
            }                                                         
+                                             
    }                                                                 
+                                             
    if ($count >= $desired) {                                         
+                                             
      print "$csv2\n";                                                
+                                             
      ++$matched;                                                     
+                                             
    }                                                                 
+                                             
  }                                                                   
+                                             
  print "$_\n\n" if $matched;                                         
+                                             
}                                                                     
+                                             
close CSV1;
[download]

I would now like to add extra functionality so that- if both the lines contain a year, in the format 1989, then the years in each csv have to match for it to be considered a positive match. However, if only one of the lines contains a year, then I would like the usual 5 matching words rule to apply and the year becomes irrelevant. Examples just to clarify. In this example field 2 contains 5 matching words but the two years (1973 + 2013) are different so this would be discounted as a match:

 2523021356, RARE TV RADIO TIMES MAGAZINE DOCTOR WHO 1973 THE THREE 3 
+DOCTORS DR JON PERTWEE, http://www.example.co.uk, 12

12278788, TV & SATELLITE WEEK 11 MAY 2013 GILLIAN ANDERSON DOCTOR WHO 
+NOT RADIO TIMES , http://www.example.co.uk, 12
[download]

In this example the years are the same AND there are 5 or more matching words so this would be a positive match:

 2523021356, RARE TV RADIO TIMES MAGAZINE DOCTOR WHO 1973 THE THREE 3 
+DOCTORS DR JON PERTWEE, http://www.example.co.uk, 12

12278788, TV & SATELLITE WEEK 11 MAY 1973 GILLIAN ANDERSON DOCTOR WHO 
+NOT RADIO TIMES , http://www.example.co.uk, 12
[download]

In this example, only one of the titles contain a year (1973), but there are also 5 or more matching words, I would like this to be considered a positive match:

 2523021356, RARE TV RADIO TIMES MAGAZINE DOCTOR WHO 1973 THE THREE 3 
+DOCTORS DR JON PERTWEE, http://www.example.co.uk, 12

12278788, TV & SATELLITE WEEK 11 MAY GILLIAN ANDERSON DOCTOR WHO NOT R
+ADIO TIMES , http://www.example.co.uk, 12
[download]

In this example, none of the titles contains a year, but 5 or more words match so this would be a positive match:

 2523021356, RARE TV RADIO TIMES MAGAZINE DOCTOR WHO THE THREE 3 DOCTO
+RS DR JON PERTWEE, http://www.example.co.uk, 12

12278788, TV & SATELLITE WEEK 11 MAY GILLIAN ANDERSON DOCTOR WHO NOT R
+ADIO TIMES , http://www.example.co.uk, 12
[download]

How can I add this functionality to the script without making wholesale changes?