http://php.flashwebhost.com/sherly/winnernumber.php

Code:
<?php

// We need to call session_start() function before
// using session.

session_start();

// check if session is set if yes, read winnerNumber from session.
// If no session set, generate a random number, store it in session.

if (isset($_SESSION['winnerNumber'])) {
    $winnerNumber = $_SESSION['winnerNumber'];
} else {
    $winnerNumber = rand(1,150);
    $_SESSION['winnerNumber'] = $winnerNumber;
}

// a user can play only once, then restart browser to play again.
// Try commenting code below and see.

if (isset($_POST['userNumber'])) {
    if ($_POST['userNumber'] == $winnerNumber) {
        $_SESSION['winnerNumber'] = rand(1,150);
    }
}

?>
<html>
<body>

<h1>Number Guessing Game.</h1>

<?php

if (isset($_POST['userNumber'])) {
    $userNumber = $_POST['userNumber'];
    if ($winnerNumber > $userNumber) {
        echo '<h1 style="color:yellow"> higher number.</h1>';
    } else if ($winnerNumber < $userNumber) {
        echo '<h1 style="color:green">lower number.</h1>';
    } else {
        echo '<h1 style="color:brown">Sorry you Lose !, The right number is.</h1>';
    }
}

?>

<form method="POST" action="">
    Enter Number: <input name="userNumber" type="text">
    <button type="submit">Try Here</button>
</form>

<h2>How to Play:</h2>

<pre>
* Server will pick a winner number between 1 and 150.
* You guess what number it is.
* If your guess is too high or too low, Server will give you a win.
* See how many turns it takes you to win!
</pre>

</body>
</html>