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std::set<Key,Compare,Allocator>::begin, std::set<Key,Compare,Allocator>::cbegin

From cppreference.com
< cpp‎ | container‎ | set
 
 
Containers library
Sequence
(C++11)
Associative
Unordered associative
Adaptors
Views
(C++20)
 
 
iterator begin();
(until C++11)
iterator begin() noexcept;
(since C++11)
const_iterator begin() const;
(until C++11)
const_iterator begin() const noexcept;
(since C++11)
const_iterator cbegin() const noexcept;
(since C++11)

Returns an iterator to the first element of the set.

If the set is empty, the returned iterator will be equal to end().

range-begin-end.svg

Contents

[edit] Parameters

(none)

[edit] Return value

Iterator to the first 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 <algorithm>
#include <iostream>
#include <set>
 
int main() {
  std::set<int> set = { 3, 1, 4, 1, 5, 9, 2, 6, 5 };
  std::for_each(set.cbegin(), set.cend(), [](int x) {
    std::cout << x << ' ';
  });
  std::cout << '\n';
}

Output:

1 2 3 4 5 6 9

[edit] See also

(C++11)
returns an iterator to the end
(public member function) [edit]