Codice PHP:
<?php 
session_start
();
$_SESSION['a'] = $_POST['a'];
$_SESSION['b'] = $_POST['b'];

?>
<form id="form1" name="form1" method="post" action="modifica.php">
  <label>
  <div align="center">
    <input name="ciccio" type="hidden" id="ciccio" value="<?php echo $a;?>" />
    <input type="submit" name="Submit" value="Invia" />
  </div>
  </label>
</form>
<form id="form2" name="form2" method="post" action="modifica.php">
  <label>
  <div align="center">
    <input name="cicci2" type="hidden" id="cicci2" value="<?php echo $b;?>" />
    <input type="submit" name="Submit2" value="Invia" />
  </div>
  </label>
</form>
o effettui l'assegnazione oppure effettui la stampa..