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

my $maxvalue;
my $value_at_3k;

while (my $line = <DATA>) {
    my ($time, $value) = split ' ', $line;
    if ($value > $maxvalue) {
        $maxvalue = $value;
    }
    unless (defined $value_at_3k) {
        if ($time > 3000) {
            $value_at_3k = $value;
        }
    }
}

print "Maxvalue was $maxvalue \n";
print "Value at 3k was $value_at_3k \n";

__DATA__
2999.98 280
2999.99 281
3000.01 285
3000.02 290
3000.03 320
3000.04 350
3000.05 325
3000.06 275
3000.07 270
3000.08 260
3000.09 235