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run code in 300+ PHP versions simultaneously
<?php $check = ['a', 'b', 'c']; $actual = ['a' => 'one', 'b' => 'two', 'c' => 'three']; $result=array_diff_key(array_flip($check), array_keys($actual)); echo '<pre>'; print_r($result);
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 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 ( [a] => 0 [b] => 1 [c] => 2 )
preferences:
110.01 ms | 2102 KiB | 4 Q