std::set<Key,Compare,Allocator>:: begin, std::set<Key,Compare,Allocator>:: cbegin
Sequence | ||||
(C++11)
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(C++26)
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(C++11)
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Associative | ||||
Unordered associative | ||||
(C++11)
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(C++11)
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(C++11)
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(C++11)
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Adaptors | ||||
(C++23)
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(C++23)
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(C++23)
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(C++23)
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Views | ||||
(C++20)
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(C++23)
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Tables | ||||
Iterator invalidation | ||||
Member function table | ||||
Non-member function table |
Member functions | |||||||||||||||||||||||||||
Non-member functions | |||||||||||||||||||||||||||
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Deduction guides (C++17) |
iterator begin
(
)
;
|
(1) | (noexcept since C++11) |
const_iterator begin
(
)
const
;
|
(2) | (noexcept since C++11) |
const_iterator cbegin
(
)
const
noexcept
;
|
(3) | (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()
.
Parameters
(none)
Return value
Iterator to the first element.
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.
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
See also
(C++11)
|
returns an iterator to the end
(public member function) |
(C++11)
(C++14)
|
returns an iterator to the beginning of a container or array
(function template) |