operator+(std::reverse_iterator)

Defined in header <iterator> 
template< class Iter > 
reverse_iterator<Iter> 
    operator+( typename reverse_iterator<Iter>::difference_type n,
               const reverse_iterator<Iter>& it );
 (until C++17) 
template< class Iter > 
constexpr reverse_iterator<Iter> 
    operator+( typename reverse_iterator<Iter>::difference_type n,
               const reverse_iterator<Iter>& it );
 (since C++17)

Returns the iterator it incremented by n.

Parameters

n - the number of positions to increment the iterator
it - the iterator adaptor to increment

Return value

The incremented iterator, that is reverse_iterator<Iter>(it.base() - n).

Example

#include <iostream>
#include <iterator>
#include <list>
#include <vector>
 
int main()
{
    {
        std::vector v{0, 1, 2, 3};
        std::reverse_iterator<std::vector<int>::iterator>
            ri1{std::reverse_iterator{v.rbegin()}};
        std::cout << *ri1 << ' '; // 3
        std::reverse_iterator<std::vector<int>::iterator> ri2{2 + ri1};
        std::cout << *ri2 << ' '; // 1
    }
    {
        std::list l{5, 6, 7, 8};
        std::reverse_iterator<std::list<int>::iterator>
            ri1{std::reverse_iterator{l.rbegin()}};
        std::cout << *ri1 << '\n'; // 8
    //  auto ri2{2 + ri1}; // error: the underlying iterator does
                           // not model the random access iterator
    }
}

Output:

3 1 8

See also

advances or decrements the iterator
(public member function)
computes the distance between two iterator adaptors
(function template)

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