3. | stats  

#!/usr/bin/perl

use 5.010;
use strict;
use warnings;
use autodie;

use Statistics::Descriptive;

my $stat = Statistics::Descriptive::Full->new();

while(<>) {
    chomp;
    $stat->add_data($_);
}

if($stat->count == 0) {
    print "No data\n";
    exit;
}

printf("Total:    %8u\n",    $stat->sum());
printf("Count:    %8u\n",    $stat->count());
printf("Mean:     %12.3f\n", $stat->mean());
printf("Median:   %12.3f\n", $stat->median());
printf("Std-dev:  %12.3f\n", $stat->standard_deviation());
printf("Minimum:  %12.3f\n", $stat->min());
printf("Maximum:  %12.3f\n", $stat->max());
printf("Variance: %12.3f\n", $stat->variance());