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<?php $configArray = array( 'grand_total' => array( 'before' => array(), '_code' => 'grand_total', ), 'discount' => array( 'before' => array('grand_total'), '_code' => 'discount', ), ); reset($configArray); $element = current($configArray); foreach ($configArray as $code => $data) { foreach ($data['before'] as $beforeCode) { if (!isset($configArray[$beforeCode])) { continue; } $configArray[$code]['before'] = array_unique( array_merge( $configArray[$code]['before'], $configArray[$beforeCode]['before'] ) ); } } print_r($configArray);

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