std::unordered_multimap::empty
Материал из cppreference.com
< cpp | container | unordered multimap
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| bool empty() const; |
(начиная с C++11) | |
Проверки, если контейнер не имеет элементов, т.е. является ли begin() == end().
Original:
Checks if the container has no elements, i.e. whether begin() == end().
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Содержание |
[править] Параметры
(Нет)
Original:
(none)
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[править] Возвращаемое значение
true если контейнер пуст, false иначе
Original:
true if the container is empty, false otherwise
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[править] Исключения
[править] Сложность
Constant
Original:
Constant
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[править] Пример
Следующий код использует
empty, чтобы проверить, std::unordered_multimap<int> содержит никаких элементов
Original:
The following code uses
empty to check if a std::unordered_multimap<int> contains any elements:
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#include <unordered_multimap> #include <iostream> int main() { std::unordered_multimap<int> numbers; std::cout << "Initially, numbers.empty(): " << numbers.empty() << '\n'; numbers.push_back(42); numbers.push_back(13317); std::cout << "After adding elements, numbers.empty(): " << numbers.empty() << '\n'; }
Вывод:
Initially, numbers.empty(): 1 After adding elements, numbers.empty(): 0
See also
| возвращает количество элементов Original: returns the number of elements The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (public функция-член) | |
