`// 颜色数组
$colors = array('红色', '蓝色', '绿色');
// 尺寸数组
$sizes = array('S', 'M', 'L');
// 版本数组
$versions = array('V1', 'V2', 'V3');

// 组合数组
$combinations = array();
foreach ($colors as $color) {
    foreach ($sizes as $size) {
        foreach ($versions as $version) {
            $combinations[] = array('颜色' => $color, '尺寸' => $size, '版本' => $version);
        }
    }
}

// 笛卡尔积操作
function cartesianProduct($arr) {
    $result = array();
    foreach ($arr as $key => $values) {
        if (empty($values)) {
            continue;
        }
        if (empty($result)) {
            foreach ($values as $value) {
                $result[] = array($key => $value);
            }
        } else {
            $append = array();
            foreach ($result as &$product) {
                $product[$key] = array_shift($values);
                $copy = $product;
                foreach ($values as $item) {
                    $copy[$key] = $item;
                    $append[] = $copy;
                }
                $values = array_values($values);
            }
            $result = array_merge($result, $append);
        }
    }
    return $result;
}

// 得到sku数组
$skus = cartesianProduct($combinations);

// 输出sku数组
print_r($skus);`

`Array
(
    [0] => Array
        (
            [颜色] => 红色
            [尺寸] => S
            [版本] => V1
        )

    [1] => Array
        (
            [颜色] => 红色
            [尺寸] => S
            [版本] => V2
        )

    [2] => Array
        (
            [颜色] => 红色
            [尺寸] => S
            [版本] => V3
        )

    [3] => Array
        (
            [颜色] => 红色
            [尺寸] => M
            [版本] => V1
        )

    [4] => Array
        (
            [颜色] => 红色
            [尺寸] => M
            [版本] => V2
        )

    [5] => Array
        (
            [颜色] => 红色
            [尺寸] => M
            [版本] => V3
        )

    [6] => Array
        (
            [颜色] => 红色
            [尺寸] => L
            [版本] => V1
        )

    [7] => Array
        (
            [颜色] => 红色
            [尺寸] =>
            ...