PHP接受所有组合

好的，这是您的代码（顺便说一句，感谢您发布了这样一个有趣且具有挑战性的问题-至少对我来说… :-)）- 在给定元素数组的情况下，对所有可能的排列
使用递归 （按N））

代码：

<?phpfunction permutations($arr,$n){     $res = array();     foreach ($arr as $w)     {if ($n==1) $res[] = $w;else{      $perms = permutations($arr,$n-1);      foreach ($perms as $p)      {$res[] = $w." ".$p;      } }     }     return $res;}// Your array$words = array('cat','dog','fish');// Get permutation by groups of 3 elements$pe = permutations($words,3);// Print it outprint_r($pe);?>

输出：

Array(    [0] => cat cat cat    [1] => cat cat dog    [2] => cat cat fish    [3] => cat dog cat    [4] => cat dog dog    [5] => cat dog fish    [6] => cat fish cat    [7] => cat fish dog    [8] => cat fish fish    [9] => dog cat cat    [10] => dog cat dog    [11] => dog cat fish    [12] => dog dog cat    [13] => dog dog dog    [14] => dog dog fish    [15] => dog fish cat    [16] => dog fish dog    [17] => dog fish fish    [18] => fish cat cat    [19] => fish cat dog    [20] => fish cat fish    [21] => fish dog cat    [22] => fish dog dog    [23] => fish dog fish    [24] => fish fish cat    [25] => fish fish dog    [26] => fish fish fish)

提示： 通过

permutations($words,2)