3v4l.org

run code in 300+ PHP versions simultaneously
<?php function flatten_array($array, $flat = array()) { foreach($array as $k=>$v){ $k = strval($k); if(!is_array($v)){ $i = 0; while(true){ $i++; $key = $k."-".strval($i); if(!isset($flat[$key])) break; } $flat[$key] = $v; }else{ $flat = flatten_array($v, $flat); } } return $flat; } // this line generates a 10x10 multi-d array $a = array_fill(0, 10, array_fill(0, 10, 0)); $flat_array = flatten_array($a); var_dump($flat_array);

preferences:
49.5 ms | 402 KiB | 5 Q