Consider using an XML parser. eg XML:Twig. 
#!perl
use strict;
use warnings;
use XML::Twig;
my $filename = 'trec7_4collections.txt';

our $num;
my $fh;
for $num (351..354){
  open $fh,'>',$num.'.xml' or die "$!";
  my $twig = XML::Twig->new(
    twig_handlers => { query => \&query },
    pretty_print=>'indented'
  );
  $twig->parsefile($filename);
  $twig->flush($fh);
  print "Created $num.xml\n";
} 

sub query { 
  my( $twig, $e) = @_;
  my $n = $e->first_child_text('number');
  $e->cut if ($n ne $num);
}

[download]
poj

In reply to Re^2: RAM, " by poj
in thread Make a perl script by taking specific lines from a txt file by nimpoura

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