object oriented

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<html>
    <head>
      <title> Introduction to Object-Oriented Programming </title>
      <link type='text/css' rel='stylesheet' href='style.css'/>
    </head>
    <body>
    <div class="malam">
      <p>
      <?php
        // The code below creates the class
        class Person {
            // Creating some properties (variables tied to an object)
            public $isAlive = true;
            public $firstname;
            public $lastname;
            public $age;

            // Assigning the values
            public function __construct($firstname, $lastname, $age) {
              $this->firstname = $firstname;
              $this->lastname = $lastname;
              $this->age = $age;
            }

            // Creating a method (function tied to an object)
            public function greet() {
              return "Hello, my name is " . $this->firstname . " " . $this->lastname . ". Nice to meet you! :-)";
            }
          }

        // Creating a new person called "boring 12345", who is 12345 years old ;-)
        $me = new Person('boring', '12345', 12345);

        // Printing out, what the greet method returns
        echo $me->greet();
        ?>
        </p>
        </div>
    </body>
</html>