#!/usr/bin/perl 
use strict;
use warnings;

my $element = 1;
my $top = 3;

my %matchings;
while (<DATA>) {
 my %seen;
 my @current_row = grep { !$seen{$_} } split ' ',$_; 

 while ( @current_row ) {
  my $temp = pop @current_row;
  for ( @current_row ) { 
   $matchings{$_}{$temp}++;
   $matchings{$temp}{$_}++;
  }
 } 
}

print "(" . 
  join(",", to_list(\%{$matchings{$element}},$top)) . 
  ")\n";

sub top_list {
 my ($hash,$min_amount) = @_; 
 return "ELEMENT WAS NOT FOUND" unless keys %$hash;

 my @max_array = sort{$hash->{$b} <=> $hash->{$a}} keys %$hash;

 my @return_array;
 while( @return_array < $top ) {
  return @return_array unless @max_array;
  push @return_array, shift @max_array;

   while ( $hash->{$return_array[$#return_array]} == $hash->{$max_arra
+y[0]} ) {
    push @return_array, shift @max_array; 
    last unless @max_array;
   }
 }
 return @return_array;
}

__DATA__
2 4 5 7 8 10 
1 2 5 6 7 9 
2 6 7 8 9 10 
1 3 5 10 
1 3 4 5 6 8 9 
1 2 4 6 
1 2 4 5 7 10 
1 3 4 6 7 8 9
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