Difference between revisions of "cpp/container/vector/size"
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Revision as of 05:13, 7 May 2015
| size_type size() const; |
(noexcept since C++11) (constexpr since C++20) |
|
Returns the number of elements in the container, i.e. std::distance(begin(), end()).
Contents |
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::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); }
See also
| returns the number of elements that can be held in currently allocated storage (public member function) | |
| checks whether the container is empty (public member function) | |
| returns the maximum possible number of elements (public member function) | |
| changes the number of elements stored (public member function) | |
| (C++17)(C++20) |
returns the size of a container or array (function template) |
