从 STL 优先级队列创建最小堆 [英] Creating Min Heap from STL Priority Queue

问题描述

我正在从 stl 优先级队列创建一个最小堆.这是我正在使用的课程.

I am creating a min heap from stl priority queue. Here is my class which I am using.

class Plane
{
  private :
    int id ;
    int fuel ;
 public:
    Plane():id(0), fuel(0){}
    Plane(const int _id, const int _fuel):id(_id), fuel(_fuel) {}

    bool operator > (const Plane &obj)
    {
        return ( this->fuel > obj.fuel ? true : false ) ;
    }

};

在 main 中，我因此实例化了一个对象.

In main I instantiate an object thus.

 priority_queue<Plane*, vector<Plane*>, Plane> pq1 ;
 pq1.push(new Plane(0, 0)) ;

我从 xutility 收到一个我无法理解的错误.

I am getting an error from xutility which I am unable to understand.

d:\microsoft Visual Studio 10.0\vc\include\xutility(674): error C2064: term 不计算为采用 2 个参数的函数

d:\microsoft visual studio 10.0\vc\include\xutility(674): error C2064: term does not evaluate to a function taking 2 arguments

对其解决方案的任何帮助将不胜感激.

Any help to its solution would be appreciated.

推荐答案

第三个模板参数必须是一个采用 teo Plane* 的二元函子.您的 Plane 类没有提供.

The third template parameter must be a binary functor taking teo Plane*. Your Plane class does not provide that.

你需要某种形式的东西

struct CompPlanePtrs
{
  bool operator()(const Plane* lhs, const Plane* rhs) const {
    return lhs->fuel > rhs->fuel ;
  }
};

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