按模板生成组合

收集了一些方法，用来生产域名然后查询注册信息。

<?php

ini_set('memory_limit','10000M');

function combinations($arrays, $i = 0) {

    if (!isset($arrays[$i])) {

        return array();

    }

    if ($i == count($arrays) - 1) {

        return $arrays[$i];

    }

    //     get combinations from subsequent arrays

        $tmp = combinations($arrays, $i + 1);

    $result = array();

    //     concat each array from tmp with each element from $arrays[$i]

        foreach ($arrays[$i] as $v) {

        foreach ($tmp as $t) {

            $result[] = is_array($t) ?

                            array_merge(array($v), $t) :

                            array($v, $t);

        }

    }

    return $result;

}

/**

* Generate all the possible combinations among a set of nested arrays.

 *

 * @param array $data  The entrypoint array container.

 * @param array $all   The final container (used internally).

 * @param array $group The sub container (used internally).

 * @param mixed $val   The value to append (used internally).

 * @param int   $i     The key index (used internally).

 */

 function generate_combinations(array $data, array &$all = array(), array $group = array(), $value = null, $i = 0)

 {

    $keys = array_keys($data);

    if (isset($value) === true) {

        array_push($group, $value);

    }

    if ($i >= count($data)) {

        array_push($all, $group);

    }

    else {

        $currentKey     = $keys[$i];

        $currentElement = $data[$currentKey];

        foreach ($currentElement as $val) {

            generate_combinations($data, $all, $group, $val, $i + 1);

        }

    }

    return $all;

}

function cartesian_product($a) {

    $result = array(array());

    foreach ($a as $list) {

        $_tmp = array();

        foreach ($result as $result_item) {

            foreach ($list as $list_item) {

                $_tmp[] = array_merge($result_item, array($list_item));

            }

        }

        $result = $_tmp;

    }

    return $result;

}

function get_combinations($arrays) {

    $result = array(array());

    foreach ($arrays as $property => $property_values) {

        $tmp = array();

        foreach ($result as $result_item) {

            foreach ($property_values as $property_value) {

                $tmp[] = array_merge($result_item, array($property => $property_value));

            }

        }

        $result = $tmp;

    }

    return $result;

}

$data = array(

    range('a', 'z'),

    range('a', 'z'),

    range('a', 'z'),

    range('a', 'z'),

    range('a', 'z'),

);

$combos = generate_combinations($data);

echo sizeof($combos);

echo "\n";

echo "not real: ".(memory_get_peak_usage(false)/1024/1024)." MiB\n";

echo "real: ".(memory_get_peak_usage(true)/1024/1024)." MiB\n\n";