PHP将数组随机匹配到自身[重复]

Question

样本数组：

$player = array("lawrence","joey","jason","joel","bianca","paulo","albert");

我想将一个数组与自身匹配，这样它就可以从自身获取一个值，而不会得到一个重复的值：

"lawrence" => "lawrence"; //must not contain itself
"joey" => "lawrence"; //must not assign value already assigned to that value

简而言之： 这就像一个交换礼物算法

Answer 1

我发现了这个帖子：Using PHP, randomly pair up group of items, not pairing any with itself, no direct pairings

而且上面的答案看起来很不错：https://stackoverflow.com/a/3758775/623952

// result array
$res = array();
// get first element and save it
$first = $ele1 = array_shift($arr);
while(count($arr)) {
    // get random element
    $ele2 = array_rand($arr);
    // associate elements
    $res[$ele1] = $arr[$ele2];
    // random element becomes next element
    $ele1 = $arr[$ele2];
    // delete the random element
    array_splice($arr, $ele2, 1);
}
// associate last element woth the first one
$res[$ele1] = $first;

这给了我：

Array
(
    [lawrence] => joel
    [joel] => joey
    [joey] => jason
    [jason] => paulo
    [paulo] => albert
    [albert] => bianca
    [bianca] => lawrence
)

您可能需要在那里进行检查，以查看您的礼物交换中是否“该人选择了自己”。

Answer 2

$player = array("lawrence","joey","jason","joel","bianca","paulo","albert");
shuffle($player);
$player2 = $player;
array_unshift($player2, array_pop($player2));

$combined = array_combine($player, $player2);

随机播放，将其转置 1 以创建有保证的唯一匹配，重新组合。