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<?php $data = [1, 63, 1]; $data = array_filter($data, function ($value) use ($data) { return !(array_count_values($data)[$value] > 1); }); print_r($data);
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.26, 8.4.1 - 8.4.13
Array ( [1] => 63 )

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