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std::unordered_set<Key,Hash,KeyEqual,Allocator>::end, std::unordered_set<Key,Hash,KeyEqual,Allocator>::cend

From cppreference.com
 
 
Containers library
Sequence
(C++11)
Associative
Unordered associative
Adaptors
Views
(C++20)
 
 
iterator end() noexcept;
(since C++11)
const_iterator end() const noexcept;
(since C++11)
const_iterator cend() const noexcept;
(since C++11)

Returns an iterator to the element following the last element of the unordered_set.

This element acts as a placeholder; attempting to access it results in undefined behavior.

range-begin-end.svg

Contents

[edit] Parameters

(none)

[edit] Return value

Iterator to the element following the last element.

[edit] Complexity

Constant.

[edit] Notes

Because both iterator and const_iterator are constant iterators (and may in fact be the same type), it is not possible to mutate the elements of the container through an iterator returned by any of these member functions.

[edit] Example

#include <iostream>
#include <unordered_set>
 
struct Point { double x, y; };
 
int main() {
    Point pts[3] = { {1, 0}, {2, 0}, {3, 0} };
 
    //points is a set containing the addresses of points
    std::unordered_set<Point *> points = { pts, pts + 1, pts + 2 };
 
    //Change each y-coordinate of (i, 0) from 0 into i^2 and print the point
    for(auto iter = points.begin(); iter != points.end(); ++iter){
        (*iter)->y = ((*iter)->x) * ((*iter)->x); //iter is a pointer-to-Point*
        std::cout << "(" << (*iter)->x << ", " << (*iter)->y << ") ";
    }
    std::cout << '\n';
 
    //Now using the range-based for loop, we increase each y-coordinate by 10
    for(Point * i : points) {
        i->y += 10;
        std::cout << "(" << i->x << ", " << i->y << ") ";
    }
}

Possible output:

(3, 9) (1, 1) (2, 4) 
(3, 19) (1, 11) (2, 14)

[edit] See also

returns an iterator to the beginning
(public member function) [edit]
(C++11)(C++14)
returns an iterator to the end of a container or array
(function template) [edit]