$products = [
    ['id' => 1, 'name' => 'Laptop', 'category' => 'Electronics', 'price' => 1200],
    ['id' => 2, 'name' => 'Keyboard', 'category' => 'Electronics', 'price' => 75],
    ['id' => 3, 'name' => 'Mouse', 'category' => 'Electronics', 'price' => 25],
    ['id' => 4, 'name' => 'T-Shirt', 'category' => 'Apparel', 'price' => 20],
    ['id' => 5, 'name' => 'Jeans', 'category' => 'Apparel', 'price' => 50],
    ['id' => 6, 'name' => 'Monitor', 'category' => 'Electronics', 'price' => 300],
];

$groupedByCategory = [];
foreach ($products as $product) {
    $category = $product['category'];
    if (!isset($groupedByCategory[$category])) {
        $groupedByCategory[$category] = [];
    }
    $groupedByCategory[$category][] = $product;
}

echo "Original products array:
";
print_r($products);
echo "
Grouped by category:
";
print_r($groupedByCategory);