#!/usr/bin/perl -w
use strict; # Always use strict;
open(PASSWD, '/etc/passwd') || die "Could not open /etc/passwd: $!\n";
my %where;
while (<PASSWD>)
{
	my @linesplit = split /:/;	# No need to use $line, 
					# @array1 or @array3
	@where{$linesplit[0]} = $linesplit[3];
}
close (PASSWD) || die "Error closing file: $!\n"; #Close an opened file!
foreach my $i (grep {$where{$_} > 1000} keys %where) 
{ 
	system ("find '/home/u1' -user $i -print > $i");
}