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<?php $entities = [ ['name' => 'Answer', 'relations' => ['AnswerGroup']], ['name' => 'AnswerGroup', 'relations' => []], ['name' => 'Condition', 'relations' => ['Question']], ['name' => 'Notion', 'relations' => []], ['name' => 'Question', 'relations' => ['Theme', 'AnswerGroup', 'Notion']], ['name' => 'Theme', 'relations' => []], ]; function list_dependents($entity, $entities) { $sorted = array(); sort($entity['relations']); foreach ($entity['relations'] as $r) { $sorted = array_merge($sorted, list_dependents($entities[array_search($r, array_column($entities, 'name'))], $entities)); } $sorted = array_merge($sorted, array($entity['name'])); return $sorted; } $sorted = array(); foreach ($entities as $entity) { $sorted = array_merge($sorted, list_dependents($entity, $entities)); } $sorted = array_values(array_unique($sorted)); print_r($sorted);

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19.79 ms | 411 KiB | 5 Q