php二分查找

<?
// 二分查找算法
function twoSerach($array, $key, $low, $hight) {
  $mid = ($low + $hight) / 2;
  while($low <= $hight) {
    if ($array[$mid] > $key) {
      $hight = $mid;
    } else if ($array[$mid] < $key) {
      $low = $mid;
    } else {
      return $key;
    }
    return 0;
  }
}

$obj = array(1, 3, 5, 7, 9, 11,13);

$result = twoSerach($obj, 7, 0, count($obj));
echo $result;