C++中cbegin迭代器學習

轉自：https://cplusplus.com/reference/vector/vector/cbegin/

1.例子

返回一個指向容器首個元素的常量型別迭代器const_iterator:

int main() { 

  std::vector<int> myvector = {10,20,30,40,50};

  std::cout << "myvector contains:";

  for (auto it = myvector.rbegin(); it != myvector.rend(); ++it){
    //*it =5;//如果這裡嘗試要修改，那麼編譯時會報錯error: assignment of read-only location ‘it.__gnu_cxx::__normal_iterator<_Iterator, _Container>::operator*<const int*, std::vector<int> >()’

    std::cout << ' ' << *it;
  }
    cout<<endl;
    return 0;
}

而使用普通的begin()/end()可以直接透過*it修改值。