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<?php $students = [ [ "country" => "japan", "school" => "kyoto university", "name" => "Naruto Uzumaki" ], [ "country" => "usa", "school" => "harvard university", "name" => "Naruto Uzumaki" ], [ "country" => "japan", "school" => "tokyo university", "name" => "sasuke Uchiha" ], [ "country" => "japan", "school" => "tokyo university", "name" => "kakashi hatake" ], ]; $result = []; foreach ($students as $student) { extract($student); $result[$country][$school] = $student; } var_export($result);

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