Untitled

<?
  session_start();
include('connect.php');
if (isset($_POST['click'])) {
$login=@$_POST['username'];
$pas=@$_POST['password'];
$sel = "SELECT * FROM user WHERE username = '$login' and password='$pas'";
$res = mysql_query($sel);
$num = mysql_num_rows($res);
 if($num==0)
 {

}
else {
  $_SESSION['username']="makson";
  echo $_SESSION['username'];
}}
?>
<!DOCTYPE html>
<html>
<head>
  <lang="uk">
  <meta charset="windows-1251">
  <link rel="icon" type="image/png" href="/Pic/play.ico" />
  <link rel="stylesheet" href="CSS/auth.css"  type="text/css">
  <title>Max Login</title>
</head>
<body>
  <div id="control_bar">
<a href="start.php" id="linkhref">Home</a>
<a href="Cataloge.php" id="linkhref">Cataloge</a>
<a href="about.php" id="linkhref">About Us</a>
<a href="Index.php" id="linkhref">Authorization</a>
</div>
  <div class="loginbox">
<img src="/Pic/logo_man.png" class="avatar" >
<h1>Authorization</h1>
<form  method="POST">
<p>Username</p>
<input type="text" required  name="username" placeholder="Enter Username">
<p>Password</p>
<input type="password" required  name="password" placeholder="Enter Password">
<input type="submit" name="click" value="Login">
<a href="index2.php">Registration</a>
</form>
  </div>
</body>
</html>