How to Combine two arrays randomly in PHP

Question

How to combine two arrays into single one and i am requesting this in such a way that the 3rd combination array should contains one value from one array and the next one from other array and so on.. or ( it could be random) ex:

$arr1 = (1, 2, 3, 4, 5);
$arr2 = (10, 20, 30, 40, 50);

and combined array

$arr3 = (1, 10, 2, 20, 3, 30, ...);

the output you show is not random but [a1,b1,a2,b2,…,an,bn]. In other words, the elements from the source arrays a and b are added in an alternating fashion to the resulting array in the order in which they appear in the source arrays — Gordon, Dec 07 '10 at 11:54
Similar question: http://stackoverflow.com/questions/2815162/is-there-a-php-function-like-pythons-zip — orip, Mar 12 '11 at 15:25

kapa · Answer 1 · 2015-12-15T08:33:38.660

18

If it can be random, this will solve your problem:

$merged = array_merge($arr1, $arr2);
shuffle($merged);

edited Dec 15 '15 at 08:33

answered Dec 07 '10 at 11:49

kapa

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score 6 · Accepted Answer · answered Dec 07 '10 at 12:09

I also made a function for fun that will produce the exact output you had in your question. It will work regardless of the size of the two arrays.

function FosMerge($arr1, $arr2) {
    $res=array();
    $arr1=array_reverse($arr1);
    $arr2=array_reverse($arr2);
    foreach ($arr1 as $a1) {
        if (count($arr1)==0) {
            break;
        }
        array_push($res, array_pop($arr1));
        if (count($arr2)!=0) {
            array_push($res, array_pop($arr2));
        }
    }
    return array_merge($res, $arr2);
}

score 3 · Answer 3 · answered Dec 07 '10 at 11:50

3

This will return a random array:

$merged = array_merge($arr1,$arr2);
shuffle($merged);

answered Dec 07 '10 at 11:50

Jonathon Bolster

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shuffle itself will only return a boolean true/false – kapa Dec 07 '10 at 11:52
No, it won't. shuffle() doesn't return an array so your method will throw the merged array into the mist of void. – Björn Dec 07 '10 at 11:53
Ah yes. I forgot about that (oops). Thanks for pointing it out – Jonathon Bolster Dec 07 '10 at 11:56

score 1 · Answer 4 · edited Mar 03 '12 at 10:24

1

sort($arr3 = array_merge($arr1, $arr2));

array_merge() will merge your arrays into one. sort() will sort the combined array.

If you want it random instead of sorted:

shuffle($arr3 = array_merge($arr1, $arr2));

$arr3 contains the array you're looking for.

edited Mar 03 '12 at 10:24

Samuel Herzog

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answered Dec 07 '10 at 11:50

Yeroon

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sort and shuffle return a bool, the passed (referenced) array is manipulated directly. – Samuel Herzog Mar 03 '12 at 00:52

score 0 · Answer 5 · edited May 22 '11 at 22:33

0

You can use

<?php
arr3 = array_merge ($arr1 , $arr2 );
print_r(arr3);
?>

which will output in

$arr3 = (1,2,3,4,5,10,20,30,40,50)

edited May 22 '11 at 22:33

kapa

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answered Dec 07 '10 at 11:50

Wazy

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How to Combine two arrays randomly in PHP

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