Php在2D数组中找到最小值的关键字

Question

我有以下2D数组，如果[0]等于done

，我想获取no列中最小值的关键字

$graph= array(
"CityA" => array(
    "0" => "1",
    "1" => "CityC",
    "done" => "no",
    ),
"CityB" => array(
    "0" => "4",
    "1" => "CityA",
    "done" => "no",
    ),
"CityC" => array(
    "0" => "5",
    "1" => "CityA",
    "done" => "no",
    ),
);

Answer 1

试试这个，

$arr = array_map(function($v){return $v[0];}, $graph);
$key = array_keys($arr, min($arr));

Answer 2

你走了。

$tes = min( array_column( $graph, 0 ) );
$key = array_search( $tes, array_column( $graph, 0 ) );
$array_keys = array_keys($graph);

echo $array_keys[$key];

Answer 3

输入：

$graph=[
        "CityB"=>["0"=>"4","1"=>"CityA","done"=>"no"],
        "CityA"=>["0"=>"1","1"=>"CityC","done"=>"no"],
        "CityD"=>["0"=>"1","1"=>"CityD","done"=>"yes"],
        "CityC"=>["0"=>"5","1"=>"CityA","done"=>"no"]
       ];

方法：

// remove all subarrays where 'done' != 'no'
$graph=array_filter($graph,function($a){return $a['done']=='no';});

// sort array on first column in subarray ASC while preserving keys
asort($graph);

// get first key
echo key($graph);

输出：

CityA

我认为这比克里斯的方式简单。