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<?php var_dump($d = date('Y-\WW-w'), date('Y-m-d')); var_dump($t = strtotime($d)); var_dump((new DateTime('@'.$t))->format('Y-\WW-w')); var_dump((new DateTime('@'.$t))->format('Y-m-d')); var_dump(DateTime::createFromFormat('Y-\WW-w', $d));

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