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<?php $arr1 = ['o' => 'vote', 'u' => 'true']; $arr2 = ['p' => '', 'v' => 'digit']; $merged = array_merge($arr1, $arr2); $key = null; foreach($merged as $k=>$v){ if($v !== false && empty($v)){ $key = $k; unset($merged[$k]); break; } } $merged[$key] = null; echo '<pre>'; print_r($merged);
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
<pre>Array ( [o] => vote [u] => true [v] => digit [p] => )
preferences:
74.48 ms | 2007 KiB | 4 Q