我怎么使用STL算法与指针的向量 [英] how do I use STL algorithms with a vector of pointers

问题描述

我有不是由容器所拥有的指针向量。如何使用上指针的目标算法。我试图用升压的ptr_vector，但它会尝试当它超出范围，删除指针。

I have a vector of pointers that are not owned by the container. How do I use algorithms on the targets of the pointers. I tried to use boost's ptr_vector, but it tries to delete the pointers when it goes out of scope.

下面是一些code，需要工作：

Here is some code that needs to work:

vector<int*> myValues;
// ... myValues is populated
bool consistent = count(myValues.begin(), myValues.end(), myValues.front()) == myValues.size();
auto v = consistent ? myValues.front() : accumulate(myValues.begin(), myValues.end(), 0) / myValues.size();
fill(myValues.begin(), myValues.end(), v);
// etc.

我认识到，对循环的工作，但这种情况发生在一堆的地方，所以某种一元的适配器？我没能找到一个。在此先感谢！

I realize that for loops would work, but this happens in a bunch of places, so some kind of unary adapter? I wasn't able to find one. Thanks in advance!

推荐答案

您可以使用的Boost间接迭代器。当解除引用（使用的operator *（）），它适用的额外的的解引用，所以你最终由指针指向的值由引用迭代器。欲了解更多信息，你还可以看到这个问题有关解引用迭代器

You could use Boost Indirect Iterator. When dereferenced (with operator*() ), it applies an extra dereference, so you end up with the value pointed by the pointer referenced by the iterator. For more information, you can also see this question about a dereference iterator.

下面是一个简单的例子：

Here's a simple example:

std::vector<int*> vec;

vec.push_back(new int(1));
vec.push_back(new int(2));

std::copy(boost::make_indirect_iterator(vec.begin()),
          boost::make_indirect_iterator(vec.end()),
          std::ostream_iterator<int>(std::cout, " "));     // Prints 1 2

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