使用迭代器反转字符串

Question

I'm trying to reverse a string (eg change "bro" to "orb") using iterators. Unfortunately, my code doesn't work. Here's my code:

for(std::string text; std::cin >> text;){
    for(std::string::const_iterator it = text.cend() + 1; it <= text.cbegin(); --it)
        std::cout << *it;
}


return 0;}

Where did I go wrong?

Answer 1

Firstly your code isn't reversing a string, it's printing a string backwards. Not the same thing at all.

The easy way to print a string backwards would be to use a reverse iterator

for (auto it = text.rbegin(); it != text.rend(); ++it)
    std::cout << *it;

But if you want to do it with a regular iterator then the following works

auto it = text.end();
while (it > text.begin())
     std::cout << *--it;