User::getUserDepartments

public function getUserDepartments(int $userId): array
{
	$departments = [];
	$result = CUser::getList(
		'id', 'asc',
		['ID_EQUAL_EXACT' => $userId],
		['FIELDS' => ['ID'], 'SELECT' => ['UF_DEPARTMENT']]
	);

	if ($user = $result->fetch())
	{
		if (isset($user['UF_DEPARTMENT']))
		{
			$user['UF_DEPARTMENT'] = (array) $user['UF_DEPARTMENT'];
			foreach ($user['UF_DEPARTMENT'] as $dpt)
			{
				$departments[] = (int) $dpt;
			}
		}
	}

	return $departments;
}