public function showTape( $tape )
	{
		for( $i=0; $i<strlen( $tape ); $i++ )
		{
			$sign = substr( $tape, $i, 1 );
			if( $i == $this->pointer )
				$lines[] = "<td style='background: #FF7F7F'>".$sign."</td>";
			else
				$lines[] = "<td>".$sign."</td>";
		}
//		return "<code>(".$this->state.") ".implode( "", $lines)."</code><br>";
		return "<tr><td>(".$this->state.")</td>".implode( "", $lines )."</tr>";
	}