strategio/split-challenge.php

## split-challenge.php
<?php
/**
 *
 * The challenge is to split an array of integer in various groups,
 * trying to have the sum of each group closer to each other...
 *
 * split-challenge.php
 * 04-dec-2014
 *
 * @package  Divider
 * @author   Strategio <strategio@strategio.fr>
 */

Class Divider {

	private $values;
	private $split;
	private $target;

	public function __construct($values=array(), $split=1)
	{
		// Set values and split if defined
		$this->setValues($values);
		$this->setSplit($split);
	}

	/**
	 * Set values to split
	 * @param array
	 * @return Divider
	 */
	public function setValues($values)
	{
		$this->values = $values;
		return $this;
	}

	/**
	 * Set number of groups to split
	 * @param integer
	 * @return Divider
	 */
	public function setSplit($split)
	{
		// Avoid dividing by zero
		if(0 == $split)
			$split = 1;

		$this->split = abs($split);
		return $this;
	}

	/**
	 * Main method to create and dispatch the groups
	 * Then display the results
	 * @param void
	 * @return void
	 */
	public function resolve()
	{
		// Define target
		$this->target = round(array_sum($this->values) / $this->split);

		// Sort values
		asort($this->values);
		// Invert sort from biggest to smallest
		$this->values = array_reverse($this->values);

		// For each group, make iteration
		$groups = array();
		for($i=0; $i<$this->split; $i++) {
			$group = array();
			$target = $this->target;
			while ($target > 0) {

				$value = $this->_use_closer_to_target($target);
				$group[] = $value;
				$target = $target - $value;

				if(count($this->values) == 0)
					break;
			}
			$groups[$i] = $group;
		}

		// Display results
		foreach ($groups as $key => $value) {
			echo '<p>'.implode(' + ', $value).' = '.array_sum($value).'</p>';
		}
	}

	/**
	 * Find the closest number from target within
	 * the values array. Then remove this value from the array
	 * and returns it.
	 * @param integer
	 * @return integer
	 */
	private function _use_closer_to_target($target)
	{
		$best_gap = false;
		$best_gap_key = false;
		foreach ($this->values as $key => $value) {
			$gap = abs($target - $value);

			// Compare current gap to best gap
			if(false == $best_gap || $gap < $best_gap) {
				$best_gap = $gap;
				$best_gap_key = $key;
			}

			// don't go further if target reached
			if(0 == $gap)
				break;
		}

		$value = $this->values[$best_gap_key];
		unset($this->values[$best_gap_key]);
		return $value;
	}
}
?>
<html>
<head>
	<title>Defi</title>
</head>
<body>
	<form>
		<input type="text" name="values" placeholder="Values" value="<?php echo isset($_GET['values']) ? $_GET['values'] : ''; ?>" style="width:300px">
		<input type="number" name="split" placeholder="Split" value="<?php echo isset($_GET['split']) ? $_GET['split'] : '1'; ?>">
		<button name="resolve">Resolve</button>
	</form>
	<pre>
	<?php
		$values = explode(',', $_GET['values']); //array(1,14,12,8,6,5,11,9,7,2,2,4,7,1,6,2,8);
		$split = $_GET['split'];

		$divider = new Divider();
		$divider->setValues($values)->setSplit($split)->resolve();
	?>
	</pre>
</body>
</html>
	<?php
	/**
	*
	* The challenge is to split an array of integer in various groups,
	* trying to have the sum of each group closer to each other...
	*
	* split-challenge.php
	* 04-dec-2014
	*
	* @package Divider
	* @author Strategio <strategio@strategio.fr>
	*/

	Class Divider {

	private $values;
	private $split;
	private $target;

	public function __construct($values=array(), $split=1)
	{
	// Set values and split if defined
	$this->setValues($values);
	$this->setSplit($split);
	}

	/**
	* Set values to split
	* @param array
	* @return Divider
	*/
	public function setValues($values)
	{
	$this->values = $values;
	return $this;
	}

	/**
	* Set number of groups to split
	* @param integer
	* @return Divider
	*/
	public function setSplit($split)
	{
	// Avoid dividing by zero
	if(0 == $split)
	$split = 1;

	$this->split = abs($split);
	return $this;
	}

	/**
	* Main method to create and dispatch the groups
	* Then display the results
	* @param void
	* @return void
	*/
	public function resolve()
	{
	// Define target
	$this->target = round(array_sum($this->values) / $this->split);

	// Sort values
	asort($this->values);
	// Invert sort from biggest to smallest
	$this->values = array_reverse($this->values);

	// For each group, make iteration
	$groups = array();
	for($i=0; $i<$this->split; $i++) {
	$group = array();
	$target = $this->target;
	while ($target > 0) {

	$value = $this->_use_closer_to_target($target);
	$group[] = $value;
	$target = $target - $value;

	if(count($this->values) == 0)
	break;
	}
	$groups[$i] = $group;
	}

	// Display results
	foreach ($groups as $key => $value) {
	echo '<p>'.implode(' + ', $value).' = '.array_sum($value).'</p>';
	}
	}

	/**
	* Find the closest number from target within
	* the values array. Then remove this value from the array
	* and returns it.
	* @param integer
	* @return integer
	*/
	private function _use_closer_to_target($target)
	{
	$best_gap = false;
	$best_gap_key = false;
	foreach ($this->values as $key => $value) {
	$gap = abs($target - $value);

	// Compare current gap to best gap
	if(false == $best_gap \|\| $gap < $best_gap) {
	$best_gap = $gap;
	$best_gap_key = $key;
	}

	// don't go further if target reached
	if(0 == $gap)
	break;
	}

	$value = $this->values[$best_gap_key];
	unset($this->values[$best_gap_key]);
	return $value;
	}
	}
	?>
	<html>
	<head>
	<title>Defi</title>
	</head>
	<body>
	<form>
	<input type="text" name="values" placeholder="Values" value="<?php echo isset($_GET['values']) ? $_GET['values'] : ''; ?>" style="width:300px">
	<input type="number" name="split" placeholder="Split" value="<?php echo isset($_GET['split']) ? $_GET['split'] : '1'; ?>">
	<button name="resolve">Resolve</button>
	</form>
	<pre>
	<?php
	$values = explode(',', $_GET['values']); //array(1,14,12,8,6,5,11,9,7,2,2,4,7,1,6,2,8);
	$split = $_GET['split'];

	$divider = new Divider();
	$divider->setValues($values)->setSplit($split)->resolve();
	?>
	</pre>
	</body>
	</html>