class BulbRow
{
	private $row = array();
	private $iteration = 0;

	function __construct($size = 100)
	{
		$this->row = array_fill(1, $size, false);
	}

	// Go to a specified iteration.
	function GoTo($target)
	{
		// If the target is closer to 0 than to current iteration, start over
		//  from there.  If the distance is the same, it's easier not to start
		//  over.
		if($target < ($this->iteration / 2))
		{
			$this->__construct(count($this->row));
		}

		// Decide whether we're counting up or down
		$direction = ($target > $this->iteration) ? 1 : -1;

		// For each step between the current iteration and the target,
		for($i = $this->iteration; $i != $target; $i += $direction)
		{
			// Count each light to be flipped on this iteration,
			for($j = $i; $j <= 100; $j += $i)
			{
				// Flip it!
				$this->row[$j] = !$this->row[$j];
			}
		}
	}

	function PrintOut()
	{
	}
}