std::set<Key,Compare,Allocator>::begin, std::set<Key,Compare,Allocator>::cbegin
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Tables
std::set
set::beginset::cbegin
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iterator begin();
(1)
(noexcept since C++11) (constexpr since C++26)
const_iterator begin() const;
(2)
(noexcept since C++11) (constexpr since C++26)
const_iterator cbegin() const noexcept;
(3)
(since C++11) (constexpr since C++26)
Returns an iterator to the first element of *this.
If *this is empty, the returned iterator will be equal to end() .
Contents
[edit] Return value
Iterator to the first element.
[edit] Complexity
Constant.
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.
libc++ backports cbegin() to C++98 mode.
[edit] Example
Run this code
#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)(C++14)
(function template) [edit]