[PHP知识库]普通二叉树 实现索引 使用php8实测性能

直接贴代码：

<?php
ini_set('memory_limit','2024M');
$totalArr = [];




for($i=1;$i<10000000;$i++){
    $totalArr[] = rand(1,1000000);
}
$newTree = [];
$time1 = floatval(time())+floatval(microtime());
foreach ($totalArr as $v){
    $newTree = buildTree($newTree,$v);
}
$time2 = floatval(time())+floatval(microtime());


$result = findTree($newTree,9990);
$time3 = floatval(time())+floatval(microtime());
echo 'buildSpendTime: '.($time2-$time1);
echo 'FindSpendTime: '.($time3-$time2)*100;
print_r($result);
exit;
/**
 * @param $tree 旧的树的数据
 * @param $item  数据
 */
function buildTree($tree,$item){
    if($tree==[]){//第一次构建
        $tree['value'][] = $item;
    }else{
        if($item == $tree['value'][0]){
            $tree['value'][] = $item;
        }else if($item>$tree['value'][0]){//大于等于 放右边
            if(!isset($tree['right'])) {
                $tree['right'] = ['value'=>[$item]];
            }else{
                $tree['right'] = buildTree($tree['right'],$item);
            }
        }else{
            if(!isset($tree['left'])) {
                $tree['left'] = ['value'=>[$item]];
            }else{
                $tree['left'] = buildTree($tree['left'],$item);
            }
        }
    }
    return $tree;
}

/**
 * 查找树
 * @param $tree
 * @param $value
 */
function findTree($tree,$value){
        if(!$tree){
            return false;
        }else{
            if($tree['value'][0] == $value){
                return $tree['value'];
            }else if($value > $tree['value'][0]){
                if(isset($tree['right'])){
                    return findTree($tree['right'],$value);
                }else{
                    return [];
                }
            }else{//left
                if(isset($tree['left'])){
                    return findTree($tree['left'],$value);
                }else{
                    return [];
                }
            }
        }
}

运行结果
buildSpendTime: 751.73062205315FindSpendTime: 0.0063896179199219Array
(
? ? [0] => 9990
? ? [1] => 9990
? ? [2] => 9990
? ? [3] => 9990
? ? [4] => 9990
? ? [5] => 9990
? ? [6] => 9990
? ? [7] => 9990
? ? [8] => 9990
? ? [9] => 9990
? ? [10] => 9990
? ? [11] => 9990
)

Process finished with exit code 0




1000w 数据，生成+ 构建树  耗时间   751.73062205315

查找数据? ?0.0063896179199219

当然这个不是 B+树 只是普通二叉树

不过也可以看出 mysql 创建索引确实很耗时，有索引的情况下查询真的很快。