Implementation of LRU algorithm with static variable array

For an explanation of the LRU algorithm, see https://baike.baidu.com/item/LRU/1269842

Baidu Encyclopedia here gives a more detailed, and then there is an example to say

LRU (least recently used) is least recently used. Assuming that the sequence is 4 3 4 2 3 1 4 2 physical blocks have 3 then the first round 4 into memory 4 times turn 3 into memory 3 4 after 4 dial memory 4 3 after 2 dial in memory 2 4 3 after 3 into memory 3 2 4 after 1 into memory 1 3 2 (because the minimum used is 4, so drop 4 ) then 4 into memory 4 1 3 (same principle) last 2 into memory 2 4 1 also such as: Consider the following page trend: 1,2,3,4,2,1,5,6,2,1,2,3,7,6,3,2,1,2,3,61 12 2 13 3 2 14 4 3 2 12 2 4 3 11 1 2 4 35 5 1 2 46 6 5 1 22 2 6 5 11 1 2 6 52 2 1 6 53 3 2 1 67 7 3 2 16 6 7 3 23 3 6 7 22 2 3 6 71 1 2 3 62 2 1 3 63 3 2 1 66 6 3 2 1 So how do you want to achieve this effect with PHP? I give the core function as follows

<?PHPfunctionLru$into _data=""){    Static $array=Array(); $max _length= 5;//Maximum length    if(Empty($array))    {        $array[]=$into _data; }Else    {        //The description is not empty and is not empty to find        $find _index=Array_search($into _data,$array); if($find _index!==false)        {            //If you find what you found, put it to the first one .            unset($array[$find _index]);//get rid of this and take the first one.            Array_unshift($array,$into _data);//put it on the first one.}Else        {            //not finding out whether the maximum length is reached if the last one is removed            if(Count($array)==$max _length-1)            {                //reach Maximum length//Remove Last                Array_pop($array); Array_unshift($array,$into _data);//put it on the first one.}Else            {                Array_unshift($array,$into _data);//put it on the first one.            }        }        $array=array_values($array);//Array Reset    }    return $array;}?>

The calling code is as follows:

<? PHP $array=array(1,2,3,4,2,1,5,6,2,1,2,3,7,6,3,2,1,2,3,6); foreach ($array as$key$v) {    $now=lru ($v);     Echo ($v). " ". (implode("",$now)). " <br/> ";}? >

The effect is as follows:

The results are as follows:

That's what we want!

Implementation of LRU algorithm with static variable array