从C ++ std :: vector中删除元素 [英] Removing elements from C++ std::vector

问题描述

从C ++向量中移除元素的正确方法是什么？我迭代一个数组，并希望删除一些符合一定条件的元素。我被告知在遍历过程中修改它是一件坏事。

What is the proper way to remove elements from a C++ vector while iterating through it? I am iterating over an array and want to remove some elements that match a certain condition. I've been told that it's a bad thing to modify it during traversal.

我想我还应该提到这是一个指针数组，我需要释放之前

I guess I should also mention that this is an array of pointers that I need to free before removing them.

编辑：

这里是我的代码片段。

void RoutingProtocolImpl::removeAllInfinity()
{
  dv.erase(std::remove_if(dv.begin(), dv.end(), hasInfCost), dv.end()); 
}

bool RoutingProtocolImpl::hasInfCost(RoutingProtocolImpl::dv_entry *entry)
{
  if (entry->link_cost == INFINITY_COST)
  {
    free(entry);
    return true;
  }
  else
  {
    return false;
  }
}

当编译时：

I'm getting the following error when compiling:

RoutingProtocolImpl.cc:368: error: argument of type bool (RoutingProtocolImpl::)(RoutingProtocolImpl::dv_entry*)' does not matchbool (RoutingProtocolImpl::*)(RoutingProtocolImpl::dv_entry*)'

对不起，我是一个C ++ newb。

Sorry, I'm kind of a C++ newb.

推荐答案

bool IsEven (int i) 
{ 
  return (i%2) == 0; 
}

//...

std::vector<int> v;
v.push_back(1);
v.push_back(2);
v.push_back(3);
v.push_back(4);
v.erase(std::remove_if(v.begin(),v.end(),IsEven), v.end()); 
//v now contains 1 and 3

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