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

my @ranges = ('15', '28-31', '3-4', '40', '17-19');
my @totals = (0, 0);

foreach my $range (@ranges) {
	$totals[$_] += (split /-/, $range)[$_] for 0, -1;
}

print "total is between $totals[0] and $totals[-1]\n";