N个数组的笛卡尔积 [英] Cartesian Product of N arrays

问题描述

我有一个 PHP 数组，它看起来像这个例子:

I have a PHP array which looks like this example:

$array[0][0] = 'apples';
$array[0][1] = 'pears';
$array[0][2] = 'oranges';

$array[1][0] = 'steve';
$array[1][1] = 'bob';

而且我希望能够从这个表中产生这些的所有可能组合，但不重复任何组合(无论它们的位置如何)，例如这将输出

And I would like to be able to produce from this a table with every possible combination of these, but without repeating any combinations (regardless of their position), so for example this would output

Array 0            Array 1
apples             steve
apples             bob
pears              steve
pears              bob

但我希望它能够处理尽可能多的不同数组.

But I would like for this to be able to work with as many different arrays as possible.

推荐答案

这被称为笛卡尔积"，数组上的 php 手册页 http://php.net/manual/en/ref.array.php 显示了一些实现(在评论中).

this is called "cartesian product", php man page on arrays http://php.net/manual/en/ref.array.php shows some implementations (in comments).

这里还有一个:

function array_cartesian() {
    $_ = func_get_args();
    if(count($_) == 0)
        return array(array());
    $a = array_shift($_);
    $c = call_user_func_array(__FUNCTION__, $_);
    $r = array();
    foreach($a as $v)
        foreach($c as $p)
            $r[] = array_merge(array($v), $p);
    return $r;
}

$cross = array_cartesian(
    array('apples', 'pears',  'oranges'),
    array('steve', 'bob')
);

print_r($cross);

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