use strict;

print "\n\nEnter numbers, one number per line.\nEnter a blank line when all values have been entered.\n";

my @values = ();
while (my $val = <>) {
	chomp($val);
	if ($val != "0") {
		@values = (@values, $val);
	}
	elsif ($val eq "0") {
		print "Please do not enter values of zero.\n";
	}
	elsif ($val eq "") {
		last;
	}
}

my $arraysize = @values;
print "\nYou have entered $arraysize values\n\n";

my $min = minimum(@values);
my $max = maximum(@values);
my $average = average(@values);
print "The minimum you have entered is $min\n\n";
print "The maximum you have entered is $max\n\n";
print "The average of the numbers you entered is $average\n\n";

sub maximum {
	my @args = @_;
	my $max = $args[0];
	foreach my $i (@args) {
		if ($i > $max) {
			$max = $i;
		}
	}
	return $max;
}

sub minimum {
	my @things    = @_;
	my $min       = $things[0];
	foreach my $z (@things) {
		if ($z < $min) {
			$min = $z;
		}
	}
	return $min;
}

sub average {
	my @stuff = @_;
	my $sum = 0;
	($sum += $_) for @stuff;
	my $average = $sum / @stuff;
	return $average;
}