(C++17) | ||||
| Sequence | ||||
(C++11) | ||||
(C++26) | ||||
(C++26) | ||||
(C++11) | ||||
| Associative | ||||
| Unordered associative | ||||
(C++11) | ||||
(C++11) | ||||
(C++11) | ||||
(C++11) | ||||
| Adaptors | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
| Views | ||||
(C++20) | ||||
(C++23) | ||||
| Tables | ||||
| Iterator invalidation | ||||
| Member function table | ||||
| Non-member function table |
| Member types | ||||||
| Member functions | ||||||
| Non-member functions | ||||||
| ||||||
| Deduction guides(C++17) | ||||||
size_type size()constnoexcept; | (since C++11) (constexpr since C++26) | |
Returns the number of elements in the container.
Contents |
std::distance(begin(), end())
Constant.
#include <cassert>#include <unordered_map> int main(){std::unordered_map<int,char> nums{{1,'a'},{1,'b'},{2,'c'},{2,'d'}};assert(nums.size()==2);}
| checks whether the container is empty (public member function)[edit] | |
| returns the maximum possible number of elements (public member function)[edit] | |
(C++17)(C++20) | returns the size of a container or array (function template)[edit] |
