FreeBSD Manual Pages
std::vector::clear(3) C++ Standard Libary std::vector::clear(3) NAME std::vector::clear - std::vector::clear Synopsis void clear(); (until C++11) void clear() noexcept; (since C++11) (until C++20) constexpr void clear() noexcept; (since C++20) Erases all elements from the container. After this call, size() re- turns zero. Invalidates any references, pointers, or iterators referring to con- tained elements. Any past-the-end iterators are also invalidated. Leaves the capacity() of the vector unchanged (note: the standard's restriction on the changes to capacity is in the specification of vector::reserve, see [1]) Parameters (none) Return value (none) Complexity Linear in the size of the container, i.e., the number of elements. Example // Run this code #include <algorithm> #include <iostream> #include <vector> int main() { std::vector<int> container{1, 2, 3}; auto print = [](const int& n) { std::cout << " " << n; }; std::cout << "Before clear:"; std::for_each(container.begin(), container.end(), print); std::cout << "\nSize=" << container.size() << ", Capacity=" << container.capacity() << '\n'; std::cout << "Clear\n"; container.clear(); std::cout << "After clear:"; std::for_each(container.begin(), container.end(), print); std::cout << "\nSize=" << container.size() << ", Capacity=" << container.capacity() << '\n'; } Output: Before clear: 1 2 3 Size=3, Capacity=3 Clear After clear: Size=0, Capacity=3 Defect reports The following behavior-changing defect reports were applied retroac- tively to previously published C++ standards. DR Applied to Behavior as published Cor- rect behavior LWG 2231 C++11 complexity guarantee was mistakenly complex- ity reaffirmed as omitted in C++11 linear See also erase erases elements (public member function) http://cppreference.com 2022.07.31 std::vector::clear(3)
NAME | Synopsis | Parameters | Return value | Complexity | Example | Output: | See also
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::vector::clear&sektion=3&manpath=FreeBSD+Ports+15.0>