From cppreference.com
reverse_iteratorrend(); (1)(noexcept since C++11)
(constexpr since C++20)const_reverse_iteratorrend()const; (2)(noexcept since C++11)
(constexpr since C++20)const_reverse_iteratorcrend()constnoexcept; (3)(since C++11)
(constexpr since C++20)Returns a reverse iterator to the character following the last character of the reversed string. It corresponds to the character preceding the first character of the non-reversed string. This character acts as a placeholder, attempting to access it results in undefined behavior.
Parameters
(none)
Return value
Reverse iterator to the character following the last character.
Complexity
Constant.
Notes
libc++ backports crend() to C++98 mode.
Example
Run this code
#include<algorithm>#include<iostream>#include<iterator>#include<string>intmain(){std::stringp("[A man, a plan, a canal: Panama]");std::stringq;std::copy(p.crbegin(),p.crend(),std::back_inserter(q));std::cout<<"q = "<<q<<'\n';std::copy(q.crbegin(),q.crend(),p.rbegin());std::cout<<"p = "<<p<<'\n';}Output:
q = ]amanaP :lanac a ,nalp a ,nam A[ p = ]amanaP :lanac a ,nalp a ,nam A[ See also
(C++11)
returns a reverse iterator to the beginning
(public member function)
returns a reverse iterator to the end
(public member function of std::basic_string_view<CharT,Traits>)