PHP Round Robin

roundrobin.php

<?php
// evenly distribute colors across $return keys

$colors = [ 'red', 'blue', 'green', 'pink' ];
$return = [ 0,1,2,3,4,5,6,7,8,9 ];

foreach($return as $i => $loop) {
  $return[$loop] = $colors[$i % count($colors)];
}

return $return;

// output:
// array:10 [
//   0 => "red"
//   1 => "blue"
//   2 => "green"
//   3 => "pink"
//   4 => "red"
//   5 => "blue"
//   6 => "green"
//   7 => "pink"
//   8 => "red"
//   9 => "blue"
// ]