PHP面试题-答案

面试题:001
需求:
两个数组
$arr_1 = [
    ['goods_id'=>100,'goods_name'=>'商品a'],
    ['goods_id'=>101,'goods_name'=>'商品b'],
    ['goods_id'=>102,'goods_name'=>'商品c'],
    ['goods_id'=>103,'goods_name'=>'商品d'],
    ['goods_id'=>104,'goods_name'=>'商品e'],

];

$arr_2 = [
    ['goods_id'=>100,'date'=>'2018-07-11'],
    ['goods_id'=>103,'date'=>'2018-07-10'],
    ['goods_id'=>104,'date'=>'2018-07-11'],
    ['goods_id'=>105,'date'=>'2018-07-09'],
];


需求: 把数组组合成,如下
[
    ['goods_id'=>100,'goods_name'=>'商品a','date'=>'2018-07-11'],
    ['goods_id'=>101,'goods_name'=>'商品b'],
    ['goods_id'=>102,'goods_name'=>'商品c'],
    ['goods_id'=>103,'goods_name'=>'商品d','date'=>'2018-07-10'],
    ['goods_id'=>104,'goods_name'=>'商品e','date'=>'2018-07-11'],
]

不能使用两层循环,效率低

答案:
$arr_1 = [
    ['goods_id'=>100,'goods_name'=>'商品a'],
    ['goods_id'=>101,'goods_name'=>'商品b'],
    ['goods_id'=>102,'goods_name'=>'商品c'],
    ['goods_id'=>103,'goods_name'=>'商品d'],
    ['goods_id'=>104,'goods_name'=>'商品e'],
];

$arr_2 = [
    ['goods_id'=>100,'date'=>'2018-07-11'],
    ['goods_id'=>103,'date'=>'2018-07-10'],
    ['goods_id'=>104,'date'=>'2018-07-11'],
    ['goods_id'=>105,'date'=>'2018-07-09'],
];

// 转换$arr_2

$new_arr = array_column($arr_2,'date','goods_id');
foreach($arr_1 as $key=>$value){
    if(array_key_exists($value['goods_id'],$new_arr)){
        $arr_1[$key]['date'] = $new_arr[$value['goods_id']];
    }
}

echo '
';
var_dump($arr_1);