本来下午要记录的，结果VPS有点问题，超时较多，打不开没办法

代码我是复制下来了，就是网址没复制到 ，原作者自己认领吧

<?php 

class LCS {

    var $str1;

    var $str2;

    var $c = array();

    /*返回串一和串二的最长公共子序列

*/

    function getLCS($str1, $str2, $len1 = 0, $len2 = 0) {

        $this->str1 = $str1;

        $this->str2 = $str2;

        if ($len1 == 0) $len1 = strlen($str1);

        if ($len2 == 0) $len2 = strlen($str2);

        $this->initC($len1, $len2);

        return $this->printLCS($this->c, $len1 - 1, $len2 - 1);

    }

    /*返回两个串的相似度

*/

    function getSimilar($str1, $str2) {

        $len1 = strlen($str1);

        $len2 = strlen($str2);

        $len = strlen($this->getLCS($str1, $str2, $len1, $len2));

        return $len * 2 / ($len1 + $len2);

    }

    function initC($len1, $len2) {

        for ($i = 0; $i < $len1; $i++) $this->c[$i][0] = 0;

        for ($j = 0; $j < $len2; $j++) $this->c[0][$j] = 0;

        for ($i = 1; $i < $len1; $i++) {

            for ($j = 1; $j < $len2; $j++) {

                if ($this->str1[$i] == $this->str2[$j]) {

                    $this->c[$i][$j] = $this->c[$i - 1][$j - 1] + 1;

                } else if ($this->c[$i - 1][$j] >= $this->c[$i][$j - 1]) {

                    $this->c[$i][$j] = $this->c[$i - 1][$j];

                } else {

                    $this->c[$i][$j] = $this->c[$i][$j - 1];

                }

            }

        }

    }

    function printLCS($c, $i, $j) {

        if ($i == 0 || $j == 0) {

            if ($this->str1[$i] == $this->str2[$j]) return $this->str2[$j];

            else return "";

        }

        if ($this->str1[$i] == $this->str2[$j]) {

            return $this->printLCS($this->c, $i - 1, $j - 1).$this->str2[$j];

        } else if ($this->c[$i - 1][$j] >= $this->c[$i][$j - 1]) {

            return $this->printLCS($this->c, $i - 1, $j);

        } else {

            return $this->printLCS($this->c, $i, $j - 1);

        }

    }

} 



$lcs = new LCS();

//返回最长公共子序列

$lcs->getLCS("hello word","hello china");

//返回相似度

echo $lcs->getSimilar("吉林禽业公司火灾已致0人遇难","吉林宝源丰禽业公司火灾已致0人遇难");