Array combination algorithm solution

Returns the array combination algorithm PHPcodearray (2) {[8] & gt; array (2) {[0] & gt; string (2) & quot; 63 & quot; [1] & gt; string (2) & quot; 64 & quot;} [9] & gt; array (2) {[0] & gt; string (2) & quot; array combination algorithm

PHP code

  array(2) {  [8] => array(2) {    [0] => string(2) "63"    [1] => string(2) "64"  }  [9] => array(2) {    [0] => string(2) "78"    [1] => string(2) "79"  }}

How many arrays are combined between two arrays? Thank you!

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PhpNewnew has discussed this.

Http://topic.csdn.net/u/20120325/11/cb8beb24-845c-4d16-be52-92f74b21a30c.html
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This is a question about Cartesian product.

PHP code

$ar = array(  8 => array('63', '64'),  9 => array('78', '79'),);print_r(Descartes($ar));function Descartes() {  $t = func_get_args();  if(func_num_args() == 1) return call_user_func_array( __FUNCTION__, $t[0] );   $a = array_shift($t);  if(! is_array($a)) $a = array($a);  $a = array_chunk($a, 1);  do {    $r = array();    $b = array_shift($t);    if(! is_array($b)) $b = array($b);    foreach($a as $p)        foreach(array_chunk($b, 1) as $q)            $r[] = array_merge($p, $q);    $a = $r;  }while($t);  return $r;}