php计数排序算法的实现代码(附四个实例代码)(2)

class CountSort
{
  private $originalData = [];
  private $rangeMap = [];
  private $resultData = [];

  public function __construct($original = [])
  {
    $this->originalData = $original;
  }

  public function sort()
  {
    list($min, $max) = $this->calculateDataRange();
    $this->statisticNumberOfOccurrence($min, $max);
    $this->resultData = $this->generateResult();
    return $this->resultData;
  }

  protected function calculateDataRange()
  {
    $max = null;
    $min = null;

    foreach ($this->originalData as $value) {
      if (!is_null($max)) {
        if ($value > $max) {
          $max = $value;
        }
      } else {
        $max = $value;
      }

      if (!is_null($min)) {
        if ($value < $min) {
          $min = $value;
        }
      } else {
        $min = $value;
      }
    }

    return [$min, $max];
  }

  protected function statisticNumberOfOccurrence($min, $max)
  {
    for ($i = $min; $i <= $max; $i++) {
      $this->rangeMap[$i] = 0;
    }

    foreach ($this->originalData as $value) {
      $this->rangeMap[$value]++;
    }
  }

  protected function generateResult()
  {
    $result = [];

    foreach ($this->rangeMap as $key => $value) {
      if ($value != 0) {
        for ($i = 0; $i < $value; $i++) {
          array_push($result, $key);
        }
      }
    }
    return $result;
  }
}

$testData = [2, 3, 4, 3, 10, 30, 20, 15, 10, 12, 33];

$countSort = new CountSort($testData);
echo '<pre>';
var_dump($countSort->sort());