Combine multidimensional array in PHP -

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• concatenate values of n arrays in php 4 answers

any tips on how this? have array this:

array (         [a] => array(1,2)         [b] => array(4,5)         [c] => array(y,z)  ) 

and want multiply keys result this:

array (     [0]=> array (            [a]=1            [b]=4            [c]=y         )    [1]=> array (            [a]=1            [b]=4            [c]=z         )    [2]=> array (            [a]=1            [b]=5            [c]=y         )    [3]=> array (            [a]=1            [b]=5            [c]=z         )    [4]=> array (            [a]=2            [b]=4            [c]=y         )    [5]=> array (            [a]=2            [b]=4            [c]=z         )    .    .    . 

where combinations of keys present. number of keys , elements variable, , it's important preserve keys.

if knew how many keys dealing i'd this:

$return = array();  $i=0;  foreach ($array[a] $val_a) {     foreach ($array[b] $val_b) {          foreach ($array[c] $val_c) {               $return[$i][a] = $val_a;              $return[$i][b] = $val_b;              $return[$i][c] = $val_b;              $i++;         }     }  } 

i'm sure there's recursive function this, can't quite figure out how it.

ok, after looking @ barmer's solution in javascript , adapting php , structure of array, came with. seems working well!

$array = array(); $array["a"] = array (1, 2); $array["b"] = array (4, 5); $array["c"] = array ("a","b");  $keys = array_keys($array);  $indices = array(); $lengths = array();  ($i = 0; $i<count($array); $i++) {     $indices[$i] = 0;     $lengths[$i] = count($array[$keys[$i]]); }  $matches = array();  while ($indices[0] < $lengths[0]) {     $row = array();     ($i = 0; $i<count($indices); $i++) {        $row[$keys[$i]] = $array[$keys[$i]][$indices[$i]];     }     $matches[] = $row;     ($j = count($indices)-1; $j >= 0; $j--) {         $indices[$j]++;         if ($indices[$j] >= $lengths[$j] && $j != 0) {             $indices[$j] = 0;         } else {             break;         }     } }  print_r ($matches); 

result:

[   {      0: {        a: "1",        b: "4",        c: "a"        },      1: {        a: "1",        b: "4",        c: "b"        },      2: {        a: "1",        b: "5",        c: "a"       },     3: {        a: "1",        b: "5",        c: "b"        },     4: {        a: "2",        b: "4",        c: "a"        },     5: {        a: "2",        b: "4",        c: "b"        },     6: {        a: "2",        b: "5",        c: "a"        },     7: {        a: "2",        b: "5",        c: "b"        }     } ]