#!/usr/bin/perl -w

use strict;

my %item_rev;	# use this to keep track of what item and revisions are encountered

open (INPUT, $ARGV[0]) or die "Couldn't open input file '$ARGV[0]': $!\n";
while (<INPUT>) {
	# skip all lines except those starting "CADItem"
	next unless /^CADItem/;
	
	# split the line into it's component fields
	my ($item_type,$item_id,$item_revision,$relation,$datsettype,$dataset) = split /;/;
	
	if (exists $item_rev{"$item_id;$item_revision"} ) {
	  # we already found the 1st occurence of this item and revision
	} else {
	  # this must be the first occurence
	  $item_rev{"$item_id;$item_revision"} = 1;
	}
}
close INPUT;

# %item_rev now contains a unique list of items with revisions
foreach my $item_with_rev (sort keys%item_rev) { print STDOUT "$item_with_rev\n"; }