Sum Difference Multiply Divide in PHP

<?php
// Define two numbers
$num1 = 20;
$num2 = 10;

// Perform operations
$sum = $num1 + $num2;
$difference = $num1 - $num2;
$product = $num1 * $num2;

// Handle division carefully to avoid division by zero
if ($num2 != 0) {
    $quotient = $num1 / $num2;
    echo "Quotient: $quotient<br>";
} else {
    echo "Division by zero is not allowed.<br>";
}

// Display results
echo "Sum: $sum<br>";
echo "Difference: $difference<br>";
echo "Product: $product<br>";
?> 

1. Start
2. Define two numbers: num1 and num2
3. Compute sum = num1 + num2
4. Compute difference = num1 - num2
5. Compute product = num1 * num2
6. If num2 ≠ 0, compute quotient = num1 / num2
7. Display all results
8. Else, display "Division by zero is not allowed"
9. End