echo "Įveskite vardą: <input type='text' name='vardas' maxlenght='14' /><br><br>";
echo "<form action='index.php' method='post'><input type='submit' name='submit10' value='Keisti'/</form>";
if(strlen($_POST['vardas']) < 13) {
printf("<script>alert('Nepavyks!');</script>");}