diff --git a/functions.php b/functions.php
new file mode 100644
index 0000000..975700d
--- /dev/null
+++ b/functions.php
@@ -0,0 +1,46 @@
+
+<?php
+
+
+
+function fattoriale ($input){
+
+		if ($input == 1){
+			return 1;
+		} else {
+			return (fattoriale($input -1 ) * $input);
+		}
+
+}
+
+function isPrime($num) {
+    //1 is not prime. See: http://en.wikipedia.org/wiki/Prime_number#Primality_of_one
+    if($num == 1)
+        return false;
+
+    //2 is prime (the only even number that is prime)
+    if($num == 2)
+        return true;
+
+    /**
+     * if the number is divisible by two, then it's not prime and it's no longer
+     * needed to check other even numbers
+     */
+    if($num % 2 == 0) {
+        return false;
+    }
+
+    /**
+     * Checks the odd numbers. If any of them is a factor, then it returns false.
+     * The sqrt can be an aproximation, hence just for the sake of
+     * security, one rounds it to the next highest integer value.
+     */
+    for($i = 3; $i <= ceil(sqrt($num)); $i = $i + 2) {
+        if($num % $i == 0)
+            return false;
+    }
+
+    return true;
+}
+
+?>
\ No newline at end of file
diff --git a/php_3.php b/php_3.php
index c72e5e0..d94f0dc 100644
--- a/php_3.php
+++ b/php_3.php
@@ -1,7 +1,8 @@
 
 <?php
 
-include ('header.html');
+require_once ('functions.php');
+include('header.html');
 
 ///////////////////////////
 echo<<<_css
@@ -18,12 +19,37 @@ echo "\n";
 
 if ($_GET == null){
 
+print <<<_HTML
+<form method="get" action="php_3.php">
+First name: <input type="number" name="numero" autofocus required placeholder="Insert the number here" min="1" max="15" ><br>
+<input type="submit" value="Send">
+</form> 
+
+
+_HTML;
 
 
 } else {
 
+	echo "fattoriale " . fattoriale($_GET['numero']) . "\n";
+	echo "<br>";
+
+	echo "primi ";
+	for ($i = 1;$i < $_GET['numero'] ; $i++)
+	{
+		if (isPrime($i))
+			echo "$i ";
+
+	}
+	echo "<br>";
+
+	echo "tabellina ";
+	for ($i = 1;$i <= 10 ; $i++)
+	{
+			echo $i * $_GET['numero'] . " ";
+
+	}
 
-    echo "cioa";
 }
 
 
diff --git a/php_4.php b/php_4.php
new file mode 100644
index 0000000..ba481be
--- /dev/null
+++ b/php_4.php
@@ -0,0 +1,56 @@
+
+<?php
+
+require_once ('functions.php');
+include('header.html');
+
+///////////////////////////
+echo<<<_css
+
+<style>
+
+
+</style>
+
+
+_css;
+echo "\n";
+///////////////////////////
+
+
+$interi =  array (5,10,50,-20,54,100,200);
+echo "min " . min($interi) . "\n";
+echo "<br>";
+echo "min " . max($interi) . "\n";
+echo "<br>";
+echo "somma " . array_sum($interi) . "\n";
+echo "<br>";
+echo "media " . array_sum($interi)/count($interi) . "\n";
+echo "<br>";
+echo "reverse ";
+$rinteri=array_reverse($interi);
+for ($i = 0;$i<count($rinteri);$i ++)
+	echo $rinteri[$i] . " ";
+echo "\n<br>";
+for ($i = 0;$i<count($interi);$i ++)
+{
+	if ($interi[$i] < 100)
+		echo $interi[$i] . " piccolo; ";
+	else
+		echo $interi[$i] . " grande; ";
+}
+echo "\n<br>";
+
+
+
+
+
+
+
+
+include ('footer.html');
+
+
+
+
+  ?>
\ No newline at end of file
diff --git a/php_5.php b/php_5.php
new file mode 100644
index 0000000..e0f1430
--- /dev/null
+++ b/php_5.php
@@ -0,0 +1,47 @@
+
+<?php
+
+require_once ('functions.php');
+include('header.html');
+
+///////////////////////////
+echo<<<_css
+
+<style>
+
+
+</style>
+
+
+_css;
+echo "\n";
+///////////////////////////
+
+echo<<<_html
+
+
+<form method="get" action="stampa.php">
+
+Nome: <input type="text" required autofocus name="name" ><br>
+Mail: <input type="email" required name ="mail"  ><br>
+Password: <input type="password" required name ="password_1"  ><br>
+Verifica Password: <input type="password" required name ="password_2"  ><br>
+<input type="submit" value="Invia">
+
+
+</form>
+
+
+_html;
+
+
+
+
+
+
+include ('footer.html');
+
+
+
+
+  ?>
\ No newline at end of file
diff --git a/php_6.php b/php_6.php
new file mode 100644
index 0000000..7c9b033
--- /dev/null
+++ b/php_6.php
@@ -0,0 +1,82 @@
+
+<?php
+
+require_once ('functions.php');
+include('header.html');
+
+///////////////////////////
+echo<<<_css
+
+<style>
+
+input.prezzo {
+	border: 0px solid;
+	text-align: center;
+}
+
+
+
+table, td {
+
+	border: 1px solid black;
+}
+
+</style>
+_css;
+echo "\n";
+///////////////////////////
+
+
+if ($_GET == null){
+
+
+	echo<<<_html
+
+
+	<form method="get" >
+
+	Primo<input type="checkbox" name="primo" value="Primo"/> Prezzo: <input class="prezzo" type="text" name="primo_prezzo" value="100" size ="1" readonly> euro <br>
+	Secondo<input type="checkbox" name="secondo" value="Secondo"/> Prezzo: <input class="prezzo" type="text" name="secondo_prezzo" value="45" size ="1" readonly> euro <br>
+	Frutta<input type="checkbox" name="frutta" value="Frutta"/> Prezzo: <input class="prezzo" type="text" name="frutta_prezzo" value="10" size ="1" readonly> euro <br>
+	Costo servizio: <input class="prezzo" type="text" name="servizio_prezzo" value="1" size ="1" readonly> euro <br>
+	<input type="submit" value="Invia">
+
+
+	</form>
+
+
+_html;
+
+}else {
+
+	$totale = 0;
+	echo "<table>";
+
+	echo "<tr><td colspan=\"2\"> Costo Servizio " . $_GET['servizio_prezzo']  . "</td></tr>\n"; $totale+=$_GET['servizio_prezzo'];
+
+	if (array_key_exists("primo", $_GET)) {   echo "<tr><td> Primo </td><td>" . $_GET['primo_prezzo']  . "</td></tr>\n";$totale+=$_GET['primo_prezzo'];}
+	if (array_key_exists("secondo", $_GET)) {   echo "<tr><td> Secondo </td><td>" . $_GET['secondo_prezzo']  . "</td></tr>\n";$totale+=$_GET['secondo_prezzo'];} 
+	if (array_key_exists("frutta", $_GET)) {   echo "<tr><td> Frutta </td><td>" . $_GET['frutta_prezzo']  . "</td></tr>\n";$totale+=$_GET['frutta_prezzo'];}
+
+	echo "<tr><td colspan=\"2\"> Totale " . $totale  . "</td></tr>\n";
+
+
+
+	echo "</table>";
+
+
+
+
+
+}
+
+
+
+
+
+include ('footer.html');
+
+
+
+
+  ?>
\ No newline at end of file
diff --git a/php_7.php b/php_7.php
new file mode 100644
index 0000000..3fa22a8
--- /dev/null
+++ b/php_7.php
@@ -0,0 +1,100 @@
+
+<?php
+
+require_once ('functions.php');
+include('header.html');
+
+///////////////////////////
+echo<<<_css
+
+<style>
+
+h1 {
+	margin: 1.5em;
+}
+
+table {
+
+	border: 1px solid black;
+}
+
+td.upper {
+	border-bottom:1px solid black;
+
+}
+td.lower {
+	border-top:1px solid black;
+
+}
+
+
+</style>
+_css;
+echo "\n";
+///////////////////////////
+
+
+if ($_GET == null){
+
+
+	echo<<<_html
+
+
+
+<table> <tr> <td class="upper"> <h1> Scelta Utente </h1></td></tr>
+<tr> <td class="mid">
+	<form id="form" method="get" >
+
+	Nome:<input type="text" name="nome" required autofocus/> <br>
+	Password:<input type="password" name="password" required/> <br><br>
+	Quali argomenti vorresti approfondire?<br>
+	<input type="checkbox" name="op1" value="Informazioni su HTML"/> Informazioni su HTML<br>
+	<input type="checkbox" name="op2" value="Immagini"/> Immagini<br>
+	<input type="checkbox" name="op3" value="Collegamenti e url"/> Collegamenti e url<br>
+	<input type="checkbox" name="op4" value="Oggetti multimediali"/> Oggetti multimediali<br>
+	<input type="checkbox" name="op5" value="XHTML versione 1.0"/> XHTML versione 1.0<br>
+
+	</form>
+
+	</td></tr>
+
+	<tr> <td class="lower">
+	<input type="submit" value="Invia!" form="form"/> <input type="reset" value="Cancella tutto!" form="form"/> 
+
+	</td></tr>
+
+</table>
+
+_html;
+
+}else {
+
+	echo "<table>";
+
+	echo "<tr><td colspan=\"2\"> Nome " . $_GET['nome']  . " Password : " . $_GET['password'] . "</td></tr>\n";
+
+	if (array_key_exists("op1", $_GET)) {   echo "<tr><td> Approfondimento </td><td>" . $_GET['op1']  . "</td></tr>\n";}
+	if (array_key_exists("op2", $_GET)) {   echo "<tr><td> Approfondimento </td><td>" . $_GET['op2']  . "</td></tr>\n";}
+	if (array_key_exists("op3", $_GET)) {   echo "<tr><td> Approfondimento </td><td>" . $_GET['op3']  . "</td></tr>\n";}
+	if (array_key_exists("op4", $_GET)) {   echo "<tr><td> Approfondimento </td><td>" . $_GET['op4']  . "</td></tr>\n";}
+	if (array_key_exists("op5", $_GET)) {   echo "<tr><td> Approfondimento </td><td>" . $_GET['op5']  . "</td></tr>\n";}
+
+
+	echo "</table>";
+
+
+
+
+
+}
+
+
+
+
+
+include ('footer.html');
+
+
+
+
+  ?>
\ No newline at end of file
diff --git a/stampa.php b/stampa.php
new file mode 100644
index 0000000..67ba709
--- /dev/null
+++ b/stampa.php
@@ -0,0 +1,51 @@
+
+<?php
+
+require_once ('functions.php');
+include('header.html');
+
+///////////////////////////
+echo<<<_css
+
+<style>
+
+
+</style>
+
+
+_css;
+echo "\n";
+///////////////////////////
+
+
+
+if ($_GET == null)
+	echo "No data to display\n";
+else {
+
+	if ($_GET['password_1'] == $_GET['password_2'] ) {
+
+		echo "Nome " . $_GET['name'] . "\n<br>";
+		echo "Mail " . $_GET['mail'] . "\n<br>";
+		echo "Password " . $_GET['password_1'] . "\n<br>";
+
+
+	} else {
+
+		echo 'Dati Inseriti invalidi';
+	}
+
+
+
+
+}
+
+
+
+
+include ('footer.html');
+
+
+
+
+  ?>
\ No newline at end of file