$stk2 = new stack2();
        echo $stk2->c();
    }
    function b()
    {
        var_dump(xdebug_get_function_stack());
        // Displays the function's call flow or stack.
    }
}
class stack2
{
    function c()
    {
        $stk = new stack();
        //Call to class "Stack"
        echo $stk->b();
    }
}
$a = '';
$stk = new stack();
$res = $stk->a($a);
xdebug_print_function_stack('Your Message');
//To Print "Your Message" text in a message.
/* Used to Findout the time taken to execute code. */
echo '<br><br>' . xdebug_time_index() . '<br>';
//Display the start time.
for ($i = 0; $i < 100; $i++) {
    // anything.
}
echo xdebug_time_index() . '<br><br>';
//Display the end time.