What potential pitfalls should be considered when using subtraction to calculate the distance between two numbers in PHP?

When using subtraction to calculate the distance between two numbers in PHP, potential pitfalls to consider include integer overflow if the numbers are very large, resulting in incorrect distance calculations. To solve this issue, you can use the abs() function to ensure the result is always positive and avoid any negative values in the distance calculation.

// Calculate the distance between two numbers
$num1 = 10;
$num2 = 5;

$distance = abs($num1 - $num2);

echo "The distance between $num1 and $num2 is: $distance";