PHP form only posting last value in a series of inputs - php

Question

Attached are pictures of my code. I am trying to pass the index.php value (either 4 or 8) of whichever button named 'num' is clicked to chooseSnacks.php and echo the variable $snacks.
The problem is that it only passes the last valued input in the form (which is 8) no matter if I click on 4 or 8. I reversed the order of the inputs just to double check, and when I did so I could only get the value 4 to pass no matter what I clicked.
Inputs on index.php
<div class="pricing-button">
<form method="POST" action="ChooseSnacks.php">
<input class="btn btn-primary btn-md btn-square" onclick="change('19.99')" type="text" value = "4" name="num[]" readonly></a>
<input class="btn btn-primary btn-md btn-square" onclick="change('25.00')" type="text" value = "8" name="num[]" readonly></a>
</div>
Submit button on index.php
<input class="btn btn-primary btn-lg btn-square" type="Submit" name="Submit" id="Submit" value='Submit'>
Session start on chooseSnacks.php
<?php
session_start();
$snacks = $_POST['num[]'];
?>
echo the variable
<div class="categories">
<h3>Your Carepackage</h3>
<p> <?php echo $snacks; ?> Snacks Every <?php echo $snacksNum; ?> </p> </div

Answer 1

In regards to $_POST['num[]']; you need to remove the [] from in there, because you already declared them as an array in name="num[]".
You then need to use a foreach($_POST['num'] as $var) and checking if they are not empty.
I used a ternary operator for that.
For example:
<div class="pricing-button">
<form method="POST" action="">
<input class="btn btn-primary btn-md btn-square" onclick="change('19.99')" type="text" value = "4" name="num[]" readonly></a>
<input class="btn btn-primary btn-md btn-square" onclick="change('25.00')" type="text" value = "8" name="num[]" readonly></a>
<input type="submit" name="Submit" value="Submit">
</div>
<?php
$inputs = !empty($_POST['num']) ? $_POST['num'] : array();
foreach($inputs as $value) {
echo $value . "<br>";
}
which will echo: (as tested)
4
8
I'm unsure as to what onclick="change('19.99')" etc. is supposed to react as though and the need for sessions where you started the session.

Answer 2

Well your input type is TEXT so it overrides the last value.
If you want the user to choose an option you should change the type to RADIO, OR set the value and name to blank and change it with javascript