std::vector::operator[]

 

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std::vector

Член функций Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

vector::vector

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Элемент доступа Original: Element access The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

vector::at

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Итераторы Original: Iterators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

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Потенциала Original: Capacity The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

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reference       operator[]( size_type pos );
const_reference operator[]( size_type pos ) const;

Возвращает ссылку на элемент в указанное место pos. Нет границ, выполняется проверка.

Original:

Returns a reference to the element at specified location pos. No bounds checking is performed.

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Параметры

pos

-

Положение элемента, чтобы вернуться Original: position of the element to return The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

Возвращаемое значение

ссылка на запрашиваемый элемент

Original:

reference to the requested element

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Сложность

Constant

Original:

Constant

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Пример

Следующий код использует operator[] читать и писать std::vector<int>

Original:

The following code uses operator[] read from and write to a std::vector<int>:

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#include <vector>
#include <iostream>
 
int main()
{
    std::vector<int> numbers {2, 4, 6, 8};
 
    std::cout << "Second element: " << numbers[1] << '\n';
 
    numbers[0] = 5;
 
    std::cout << "All numbers:";
    for (auto i : numbers) {
        std::cout << ' ' << i;
    }
    std::cout << '\n';
}

Вывод:

Second element: 4
All numbers: 5 4 6 8

См. также

at	предоставляет доступ к указанному элементу с проверкой индекса (public функция-член)