#!/user/bin/perl
use strict;
use warnings;
use Time::HiRes qw(gettimeofday tv_interval);
sub sum {
   my ($numbers_ref) = @_;
   my $sum = 0;
   foreach my $num (@$numbers_ref){ $sum += $num };
   return $sum;
} # end sub sum()
my $t0 = [gettimeofday];
print sum([1..100_000]);
print "\n";
my $t1 = [gettimeofday];
my $elapsed = tv_interval($t0, $t1);
print "\n";
print "Elapsed time: $elapsed seconds\n";
exit(0);