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

my $count=0;

while (<DATA>) 
{
   # default split is /\s+/ which includes \t
   # white space characters are: \t\f\r\n and space

   my ($perfNum) = split;        #first token of split
   $count++ if ($perfNum > 600);
}

print "count of perfNums > 600: $count\n";

#prints: count of perfNums > 600: 3

__DATA__
10  alpha
30  bravo
60  charlie
100 delta
500 echo
600 foxtrot
4   golf
22  hotel
900 igloo
800 juliet
999 kilo
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