All permutations from multiple arrays

orange99

I've seen other messages about this type of thing, but not specifically for what I want to do...

I have multiple arrays of single characters. e.g.

$array1 = ('a', 'b', 'c')
$array2 = ('1', '2','3','4')
$array3 = ('x','y')

and I want to find all of the possible permutations (as strings in an array) for taking one character from each string (in order). So the result for the above would be :

$result[0] = 'a1x'
$result[1] = 'a1y'
$result[2] = 'a2x'
$result[3] = 'a2y'
and so on to
$result[n] = 'c4x'

The alogrithm needs to be able to take up to ten arrays (defined at run time) each with up to ten elements in. The number of elements will vary from array to array. I am thinking that this needs recursion, but I am stuck as a) recursion never was my hot subject! and b) I have only been able to find solutions for getting all of the permutations from one individual array (and I can't get my head around making those work for multiple arrays).

Any help or pointers is (as always!) much appreciated

Rob

sidney

<?php
$array1 = array('a', 'b', 'c') ;
$array2 = array('1', '2','3','4'); 
$array3 = array('x','y');
$array4=array('');
$array5=array('');
$array6=array(1,2,3,4,5,6,7);
$array7=array('');
$array8=array('');
$array9=array('');
$array10=array('');
$val1='';
$val2='';
$val3='';
$val4='';
$val5='';
$val6='';
$val7='';
$val8='';
$val9='';
$val10='';
foreach($array1 as $val1)
	foreach($array2 as $val2)
		foreach($array3 as $val3)
			foreach($array4 as $val4)
				foreach($array5 as $val5)
					foreach($array6 as $val6)
						foreach($array7 as $val7)
							foreach($array8 as $val8)
								foreach($array9 as $val9)
									foreach($array10 as $val10)
			$result[]= $val1.$val2.$val3.$val4.$val5.$val6.$val7.$val8.$val9.$val10;
//diplay output
echo '<pre>';
var_dump($result);
echo '</pre>';

orange99

Thanks for that Sidney. I had thought about some kind of foreach based structure, but I couldn't figure out how to deal with different numbers of arrays. It didn't cross my mind that I could just include them as empty arrays so that foreach would effectively skip them. Doh!.

Thanks again.