use warnings;
use strict;

my $i = $#ARGV;

if ($ARGV[0] eq "add") {
	my $rtn = add($ARGV[1]..$ARGV[$i]);
	print "The sum is: $rtn";
}

elsif ($ARGV[0] eq "multiply"){
	my $rtn = multiply($ARGV[1]..$ARGV[$i]);
	print "Their product is: $rtn";
}

sub add {
	my ($sum);
	$sum=0;
	foreach $_(@_) {
		$sum +=$_;
	}
	return $sum;
}

sub multiply {
	my $product=1;
	foreach $_(@_) {
		$product*=$_;
	}
	return $product;
}