PHP program to create a case in-sensitive constant using define() function

Program/Source Code:

The source code to create a case in-sensitive constant using the define() function is given below. The given program is compiled and executed successfully.

<?php
//PHP program to create a constant
//using define() function.

define(PI, 3.14);

$radius = 5;

$area = PI * $radius * $radius;

print ("Area of circle: " . $area);
?>

Output:

Area of circle: 78.5

Explanation:

In the above program, we created a case insensitive constant PI using the define() function that contains value 3.14. Then we created a local variable $radius initialized with 5. Then calculate the area of the circle and print the result on the console screen.