将向量< T> :: iterator与向量< T> :: reverse_iterator进行比较 [英] Compare vector<T>::iterator with vector<T>::reverse_iterator

问题描述

我正在做一个练习，我有一个向量，我正在写一个反向算法，通过使用一个反向和一个正向（正向）迭代器来反转向量的内容。但是，我无法比较迭代器。

I am working on an exercise where I have a vector and I am writing my own reverse algorithm by using a reverse and a normal (forward) iterator to reverse the content of the vector. However, I am not able to compare the iterators.

int vals[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 };
vector<int> numbers(vals, vals + 10);

vector<int>::iterator       start = numbers.begin();
vector<int>::reverse_iterator end = numbers.rend();

我有一个先前的算法通过使用两个迭代器逆向向量，能够使用！=运算符在它们之间进行比较。我的猜测是获得底层的指针或索引在向量中彼此，但如何获得指针/索引？

I have a previous algorithm for reversing the vector by using two iterators, however in this task I am not able to compare them using the != operator between them. My guess would be to get the underlying pointers or indexes in the vector with each other but how do I get the pointers/index?

推荐答案

使用 base（）返回的迭代器进行比较$ c> ： it == rit.base（） - 1 。

Do a comparison using the the iterator returned by base(): it == rit.base() - 1.

这篇关于将向量< T> :: iterator与向量< T> :: reverse_iterator进行比较的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！