std::multimap<Key,T,Compare,Allocator>::rbegin, std::multimap<Key,T,Compare,Allocator>::crbegin
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std::multimap
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multimap::rbeginmultimap::crbegin
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reverse_iterator rbegin();
(1)
(noexcept since C++11) (constexpr since C++26)
const_reverse_iterator rbegin() const;
(2)
(noexcept since C++11) (constexpr since C++26)
const_reverse_iterator crbegin() const noexcept;
(3)
(since C++11) (constexpr since C++26)
Returns a reverse iterator to the first element of the reversed *this. It corresponds to the last element of the non-reversed *this.
If *this is empty, the returned iterator is equal to rend() .
Contents
[edit] Return value
Reverse iterator to the first element.
[edit] Complexity
Constant.
[edit] Notes
The underlying iterator of the returned reverse iterator is the end iterator. Hence the returned iterator is invalidated if and when the end iterator is invalidated.
libc++ backports crbegin() to C++98 mode.
[edit] Example
Run this code
#include <algorithm> #include <iostream> #include <string> #include <map> int main() { std::multimap <std::string, int> map { {"█", 1}, {"▒", 5}, {"░", 3}, {"▓", 7}, {"▓", 8}, {"░", 4}, {"▒", 6}, {"█", 2} }; std::cout << "Print out in reverse order using const reverse iterators:\n"; std::for_each (map.crbegin(), map.crend(), [](std::pair <const std::string, int> const& e) { std::cout << "{ \"" << e.first << "\", " << e.second << " };\n"; }); map.rbegin()->second = 42; // OK, non-const value is modifiable // map.crbegin()->second = 42; // Error: cannot modify the const value }
Possible output:
Print out in reverse order using const reverse iterators:
{ "▓", 8 };
{ "▓", 7 };
{ "▒", 6 };
{ "▒", 5 };
{ "░", 4 };
{ "░", 3 };
{ "█", 2 };
{ "█", 1 };[edit] See also
(C++14)
(function template) [edit]