Challenge 1 — Solution

Task: Create an associative array representing a product (name, price,
in_stock as a boolean). Encode it to JSON with json_encode(), echo it,
then decode that exact JSON string back into a PHP array with
json_decode(), and echo the price from the decoded array to confirm
round-tripping worked correctly.

<?php
    $product = [
        "name" => "Wireless Keyboard",
        "price" => 34.99,
        "in_stock" => true
    ];

    $json = json_encode($product);
    echo $json . "<br>";

    $decoded = json_decode($json, true);
    echo $decoded['price'];
?>


Output:
{"name":"Wireless Keyboard","price":34.99,"in_stock":true}
34.99

Notes:
- json_encode() converts the PHP boolean "true" into the literal JSON
  keyword "true" (no quotes) - JSON has its own native boolean type,
  distinct from a string like "yes" or the number 1.
- json_decode($json, true) passes true as the second argument
  specifically so the result comes back as a familiar associative array
  ($decoded['price']) rather than a stdClass object requiring ->price
  syntax instead.
- The round-trip confirms fidelity: $decoded['price'] is 34.99, exactly
  matching the original $product['price'] value before it was ever
  encoded - demonstrating json_encode()/json_decode() are proper
  inverses of one another for this kind of data.