std::vector<T,Allocator>::size
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size_type size() const;
(noexcept since C++11) (constexpr since C++20)
Returns the number of elements in the container.
Contents
[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]
(public member function) [edit]