std::array<T,N>::size

 

C++

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Symbols index

External libraries

 

Containers library

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array (C++11)

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std::array

Member types

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Element access

array::at

array::operator[]

array::front

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array::data

Iterators

array::beginarray::cbegin

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array::rbeginarray::crbegin

array::rendarray::crend

Capacity

array::empty

array::size

array::max_size

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array::fill

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get

std::swap

to_array (C++20)

operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)

Helper classes

tuple_size

tuple_element

Deduction guides(C++17)

 

constexpr size_type size() const noexcept;		(since C++11)

Returns the number of elements in the container, i.e. std::distance(begin(), end()).

Parameters

(none)

Return value

The number of elements in the container.

Complexity

Constant.

Example

The following code uses size to display the number of elements in a std::array:

Run this code

#include <array>
#include <iostream>
 
int main()
{ 
    std::array<int, 4> nums {1, 3, 5, 7};
 
    std::cout << "nums contains " << nums.size() << " elements.\n";
}

Output:

nums contains 4 elements.

See also

empty (C++11)	checks whether the container is empty (public member function)
max_size (C++11)	returns the maximum possible number of elements (public member function)
sizessize (C++17)(C++20)	returns the size of a container or array (function template)