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<?php $array = [1, 63, 1, 12, 64, 12]; $new = []; foreach ($array as $value) { if (count(array_keys($array, $value)) == 1) { $new[] = $value; } } var_dump($new);
Output for 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
array(2) { [0]=> int(63) [1]=> int(64) }

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