size_type size() const; | (until C++11) | |
size_type size() const noexcept; | (since C++11) (until C++20) | |
constexpr size_type size() const noexcept; | (since C++20) |
Returns the number of elements in the container, i.e. std::distance(begin(), end()).
(none).
The number of elements in the container.
Constant.
The following code uses size to display the number of elements in a std::vector<int>:
#include <vector>
#include <iostream>
int main()
{
std::vector<int> nums {1, 3, 5, 7};
std::cout << "nums contains " << nums.size() << " elements.\n";
}Output:
nums contains 4 elements.
| returns the number of elements that can be held in currently allocated storage (public member function) |
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| checks whether the container is empty (public member function) |
|
| returns the maximum possible number of elements (public member function) |
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| changes the number of elements stored (public member function) |
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(C++17)(C++20) | returns the size of a container or array (function template) |
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