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std::vector<T,Allocator>::size

From cppreference.com
< cpp‎ | container‎ | vector
 
 
 
std::vector
(until C++20)(until C++20)(until C++20)(until C++20)(until C++20)
 
size_type size() const;
(noexcept since C++11)
(constexpr since C++20)

Returns the number of elements in the container.

[edit] Return value

std::distance (begin(), end())

[edit] Complexity

Constant.

[edit] Example

The following code uses size to display the number of elements in a std::vector <int>:

Run this code
#include <cassert>
#include <vector>
 
int main()
{
 std::vector <int> nums;
 assert (nums.size() == 0);
 nums = {1, 2, 3, 4};
 assert (nums.size() == 4);
}

[edit] See also

returns the number of elements that can be held in currently allocated storage
(public member function) [edit]
checks whether the container is empty
(public member function) [edit]
returns the maximum possible number of elements
(public member function) [edit]
changes the number of elements stored
(public member function) [edit]
(C++17)(C++20)
returns the size of a container or array
(function template) [edit]
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