Its just what I though of first. You could also do: 
use strict;
use warnings;
use List::Util qw(max);

my %prns;

while (<DATA>)
{
    my ( $printer, $num, $cmd ) = split /:/;
    $prns{$num} = $printer;
}

print "Highest numbered printer is $prns{max (keys %prns) }\n";
__DATA__
M08_amvpss09_MEDIP :275:lp -damvpss09
M07_amvpss09_MEDIP :279:lp -damvpss09
M09_amvpss09_MEDIP :278:lp -damvpss09
M01_amvpss09_MEDIP :2:lp -damvpss09
M04_amvpss09_MEDIP :1000:lp -damvpss09

[download]
Something line FunkyMonk's suggestion would work as well.
Ted
--
"That which we persist in doing becomes easier, not that the task itself has become easier, but that our ability to perform it has improved."
  --Ralph Waldo Emerson

In reply to Re^3: Parsing a data file to find the highest value. by tcf03
in thread Parsing a data file to find the highest value. by misconfiguration

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