PHP實現哈希表

PHP實現哈希表

//一個簡單的哈希表實現。。。。

size;
        $this->collection = new SplFixedArray($bucketsSize);
    }

    //生成散列值，作為存儲數據的位置
    private function _hashAlgorithm($key)
    {
        $length = strlen($key);
        $hashValue = 0;
        for($i=0; $i<$length; $i++) {
            $hashValue += ord($key[$i]);
        }
        return ($hashValue%($this->size));
    }

    //在相應的位置存儲對應的值
    public function set($key, $val)
    {
        $index = $this->_hashAlgorithm($key);
        $this->collection[$index] = $val;
    }

    //根據鍵生成散列值，進而找到對應的值
    public function get($key)
    {
        $index = $this->_hashAlgorithm($key);
        return $this->collection[$index];
    }

    //刪除某個值,成功返回1，失敗返回0
    public function del($key)
    {
        $index = $this->_hashAlgorithm($key);
        if(isset($this->collection[$index])) {
            unset($this->collection[$index]);
            return 1;
        } else {
            return 0;
        }
    }

    //判斷某個值是否存在，存在返回1， 不存在返回0
    public function exist($key)
    {
        $index = $this->_hashAlgorithm($key);
        if($this->collection[$index]){
            return 1;
        } else {
            return 0;
        }
    }

    //返回key的個數
    public function size()
    {
        $size = 0;
        $length = count($this->collection);
        for($i=0; $i<$length; $i++) {
            if($this->collection[$i]) {
                $size++;
            }
        }
        return $size;
    }

    //返回value的序列
    public function val()
    {
        $size = 0;
        $length = count($this->collection);
        for($i=0; $i<$length; $i++) {
            if($this->collection[$i]) {
                echo $this->collection[$i]."
";
            }
        }
    }

    //排序輸出
    public function sort($type=1)
    {
        $length = count($this->collection);
        $temp = array();
        for($i=0; $i<$length; $i++) {
            if($this->collection[$i]) {
                $temp[] = $this->collection[$i];
            }
        }

        switch ($type) {
            case 1:
                //正常比較
                sort($temp, SORT_REGULAR);
                break;
            case 2:
                //按照數字比較
                sort($temp, SORT_NUMERIC);
                break;
            //按照字符串進行比較
            case 3:
                sort($temp, SORT_STRING);
                break;
            //根據本地字符編碼環境進行比較
            case 4:
                sort($temp, SORT_LOCALE_STRING);
                break;

        }
        echo "
";
        print_r($temp);
    }

    //逆序輸出
    public function rev($type=1)
    {
        $length = count($this->collection);
        $temp = array();
        for($i=0; $i<$length; $i++) {
            if($this->collection[$i]) {
                $temp[] = $this->collection[$i];
            }
        }

        switch ($type) {
            case 1:
                //正常比較
                rsort($temp, SORT_REGULAR);
                break;
            case 2:
                //按照數字比較
                rsort($temp, SORT_NUMERIC);
                break;
            //按照字符串進行比較
            case 3:
                rsort($temp, SORT_STRING);
                break;
            //根據本地字符編碼環境進行比較
            case 4:
                rsort($temp, SORT_LOCALE_STRING);
                break;

        }
        echo "
";
        print_r($temp);
    }


}

//簡單的測試
$list = new hashTable(200);
$list->set("zero", "zero compare");
$list->set("one", "first test");
$list->set("two", "second test");
$list->set("three", "three test");
$list->set("four", "fouth test");
echo $list->val();
echo "after sorted : 
";
$list->rev(3);