Each of your subroutines returns a value. You must capture this returned value if you want to display the results in the following print statement.

Here is your code with the small additions pointed out above

use strict;

print "\n\nEnter numbers, one number per line.\nEnter a blank line whe
+n 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;
}
[download]

Note: Code run through Perl::Tidy to clean up the formatting

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.