Untitled

<!DOCTYPE html>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

<html>
<body>
        <form METHOD="POST" ACTION="control.php">

        <br>Nom<br>
        <INPUT TYPE="TEXT" NAME="nombre">
        <br><br>Contrasenya<br>
        <INPUT TYPE="PASSWORD" NAME="contrasena"><br>

        <input type="submit" value="Login">
        </form>


</body>
</html>


<?php
$usuario = $_POST['nombre'];
$pass = $_POST['contrasena'];

mysqli_connect('localhost','root','alumne');
mysqli_select_db('examen');
$result =mysqli_query("SELECT * FROM usuaris WHERE nom='".$usuario ."' AND passwd='".$pass ."'");

if($row = mysqli_fetch_array($result)){

  if($row['contrasena'] === $pass){

    session_start();
    $_SESSION['usuario'] = $row['nom'];
    echo hola;
  }
}
else{
  echo adios;
}

 ?>